The Role of Patents and Regulatory Exclusivities in Drug Pricing

Congressional research reportJan 30, 2024

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The Role of Patents and Regulatory

Exclusivities in Drug Pricing

Updated January 30, 2024

Congressional Research Service

https://crsreports.congress.gov

R46679

SUMMARY

The Role of Patents and Regulatory

Exclusivities in Drug Pricing

Intellectual property (IP) rights play an important role in the development and pricing of

prescription drugs and biologics. To encourage innovation, IP law grants inventors exclusive

rights in a particular invention or product, potentially enabling them to charge higher-thancompetitive prices. IP rights are typically justified as necessary to allow pharmaceutical

manufacturers the ability to recoup substantial costs in research and development, including

clinical trials and other tests necessary to obtain regulatory approval from the U.S. Food and

Drug Administration (FDA). However, IP rights have been criticized as contributing to high

prices for pharmaceutical products in the United States by operating to deter or delay competition

from generic drug and biosimilar manufacturers.

R46679

January 30, 2024

Kevin J. Hickey

Legislative Attorney

Erin H. Ward

Coordinator of Research

Planning/ALD

Two main types of IP rights may protect pharmaceutical products: patents and regulatory exclusivities. Patents, which are

available for a wide range of technologies beyond pharmaceuticals, are granted by the U.S. Patent and Trademark Office

(PTO). Patents may claim chemical compounds in the pharmaceutical product, a method of using the product, a method of

making or administering the product, or a variety of other patentable inventions relating to a drug or biologic. The holder of a

valid patent generally has the exclusive right to make, use, sell, and import the invention for a term lasting approximately 20

years. Pharmaceutical patent disputes are subject to certain specialized procedures under the Hatch-Waxman Act and the

Biologics Price Competition and Innovation Act (BPCIA), which can affect when generic and biosimilar manufacturers can

market their follow-on products.

In addition to patent protection, certain pharmaceuticals, such as innovative products or those that serve particular needs, may

qualify for periods of regulatory exclusivity when they are approved or licensed by FDA. Pharmaceutical products may only

be sold in the United States after FDA has determined they are safe and effective, based on submitted data, and has approved

or licensed them. FDA generally may not accept and/or approve a generic drug or biosimilar if the pharmaceutical product

being used as a reference to show the follow-on product is safe and effective is covered by an unexpired regulatory

exclusivity. Regulatory exclusivities vary in length from six months to 12 years, depending on the basis for the exclusivity.

Because the exclusivity that IP rights provide may enable the rights holder (e.g., a brand-name drug manufacturer) to charge

higher-than-competitive prices for a period of time, rights holders may have an incentive to lengthen that time period as much

as possible. Some commentators allege that certain brand-name drug manufacturers have engaged in patenting practices that

unduly extend the period of exclusivity. Critics argue that these patenting practices are used to keep drug prices high, without

significant benefits for consumers or innovation. Such patenting practices include so-called (1) patent “evergreening,” (2)

“product hopping,” (3) “patent thickets,” and (4) “pay-for-delay” settlements. Patent “evergreening” is the alleged practice of

filing for new patents on secondary features of a pharmaceutical as earlier patents expire, thereby extending effective patent

exclusivity past the original 20-year term. “Product hopping” is the alleged practice of a brand manufacturer attempting to

switch the market to a new, similar product covered by later-expiring patents before IP rights on an existing product expire.

“Patent thickets” refer to portfolios of numerous, overlapping patents on the same pharmaceutical, which allegedly deter

competition due to the risk of infringement and the high cost of patent litigation. “Pay-for-delay” or “reverse payment”

settlements resolve patent litigation through payments or other compensation from a brand to a generic or biosimilar

manufacturer to delay generic market entry. In some cases, these settlements may be anticompetitive because they allow the

brand to continue to charge high prices without risking invalidation of its patent.

Drug manufacturers counter that their patenting practices protect new and useful inventions as Congress intended when it

created the patent system. In their view, the terms for these practices are unfairly pejorative, or, at most, describe outlier

behavior by a few companies. Defenders of these patenting practices reject their characterization as anticompetitive and

emphasize that strong patent rights encourage innovation and life-saving research and development efforts.

Congressional Research Service

The Role of Patents and Regulatory Exclusivities in Drug Pricing

Contents

IP Rights in Pharmaceuticals: Incentives for Innovation Versus Cost and Access .......................... 3

FDA Approval and Licensure of Pharmaceutical Products ............................................................. 6

New and Generic Drug Approval .............................................................................................. 7

New Drug Approval ............................................................................................................ 7

Generic Drug Approval ....................................................................................................... 9

Biological Product and Biosimilar Licensure ......................................................................... 10

Biological Products ........................................................................................................... 10

Biosimilar or Interchangeable Products ............................................................................. 11

Regulatory Exclusivities ......................................................................................................... 12

New Drugs or Biological Products ................................................................................... 12

Generic Drug and Biosimilar Exclusivities ...................................................................... 14

Other Regulatory Exclusivities ......................................................................................... 15

Securing and Enforcing Patent Protections for Pharmaceuticals .................................................. 17

Types of Pharmaceutical Patent Claims .................................................................................. 18

Patent Enforcement ................................................................................................................. 21

Rights of Patent Holders ................................................................................................... 21

Patent Term and Effective Exclusivity Periods ................................................................. 22

Defenses to Claims of Patent Infringement ...................................................................... 23

Remedies for Patent Infringement .................................................................................... 24

The Patent Trial and Appeal Board ................................................................................... 24

Compulsory Licensing ............................................................................................................ 25

Patent Dispute Procedures for Generic Drugs and Biosimilars ..................................................... 28

Rationale for Specialized Pharmaceutical Patent Procedures ................................................. 29

The Hatch-Waxman Act: Patents and Generic Drug Approval ............................................... 31

Paragraph I-IV Certifications and Interaction with FDA Approval .................................. 31

Orange Book Patent Listings ............................................................................................ 33

Section viii Statements and “Skinny Labels” ................................................................... 34

The BPCIA: The “Patent Dance” and Biosimilar Licensure................................................... 35

Antitrust Law................................................................................................................................. 39

Section 1 of the Sherman Act .................................................................................................. 40

Section 2 of the Sherman Act .................................................................................................. 41

Enforcement ............................................................................................................................ 42

Pharmaceutical Patenting Practices ............................................................................................... 42

“Evergreening” ........................................................................................................................ 44

Definition .......................................................................................................................... 44

Debate ............................................................................................................................... 45

Current Law ...................................................................................................................... 47

“Product Hopping” .................................................................................................................. 48

Definition .......................................................................................................................... 48

Debate ............................................................................................................................... 50

Current Law ...................................................................................................................... 52

“Patent Thickets”..................................................................................................................... 52

Definition .......................................................................................................................... 52

Debate ............................................................................................................................... 53

Current Law ...................................................................................................................... 55

“Pay-for-Delay” or “Reverse Payment” Settlements .............................................................. 56

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The Role of Patents and Regulatory Exclusivities in Drug Pricing

Definition .......................................................................................................................... 56

Debate ............................................................................................................................... 57

Current Law ...................................................................................................................... 58

Combinations of Practices....................................................................................................... 59

Conclusion ..................................................................................................................................... 60

Figures

Figure 1. Patent Dispute Procedures for Generic Drugs ............................................................... 32

Figure 2. Patent Dispute Procedures for Biosimilars .................................................................... 38

Tables

Table 1. Regulatory Exclusivities for Pharmaceutical Products .................................................... 16

Table 2. Summary Comparison of Patents Versus Regulatory Exclusivities ................................ 29

Table 3. Summary Comparison of the Hatch-Waxman Act and the BPCIA ................................. 39

Contacts

Author Information........................................................................................................................ 60

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The Role of Patents and Regulatory Exclusivities in Drug Pricing

T

he prices consumers pay for prescription drugs has long been of significant

congressional interest. In recent Congresses, several House and Senate committees held

hearings on drug pricing issues,1 and Members introduced dozens of bills to address the

perceived high costs of prescription drugs and other pharmaceutical products.2 Growth

in U.S. expenditures on prescription drugs—which for decades rose at double-digit rates

annually—has moderated in recent years and is projected to continue to grow by about 5.5% per

year (roughly in line with increases in general health care spending).3 Despite recent fluctuations,

consumers in the United States generally pay significantly higher prices for prescription drugs as

compared to other developed countries.4

Many factors contribute to the prices consumers pay for drugs and biologics, including demand,

manufacturing costs, research and development (R&D) costs, the terms of private health

insurance, and the involvement of a government insurance program such as Medicaid or

Medicare.5 Pharmaceutical products are often protected by intellectual property (IP) rights,6 and

1 See, e.g., The Need to Make Insulin Affordable for All Americans: Hearing Before the S. Comm. on Health, Educ.,

Labor & Pensions, 118th Cong. (2023); Lower Drug Costs Now: Expanding Access to Affordable Health Care:

Hearing Before the H. Subcomm. on Health, Employment, Labor and Pensions of the H. Comm. on Educ. & Labor,

117th Cong. (2021); Why Does the US Pay the Highest Prices in the World for Prescription Drugs?: Hearing Before

the S. Comm. On Health, Educ., Labor & Pensions, 117th Cong. (2021); Unsustainable Drug Prices: Testimony from

the CEOs (Parts I and II): Hearing Before the H. Comm. on Oversight & Reform, 116th Cong. (2020); Intellectual

Property and the Price of Prescription Drugs: Balancing Innovation and Competition: Hearing Before the S. Comm.

on the Judiciary, 116th Cong. (2019); Drug Pricing in America: A Prescription for Change (Parts I–III): Hearing

Before the S. Comm. on Fin., 116th Cong. (2019); The Cost of Rising Prescription Drug Prices, Hearing Before the H.

Ways & Means Comm., 116th Cong. (2019); Examining the Actions of Drug Companies in Raising Prescription Drug

Prices: Hearing Before the H. Comm. on Oversight & Reform, 116th Cong. (2019).

Both the Biden and Trump administrations released plans and used executive authorities to plans to address rising drug

prices. See generally U.S. DEP’T OF HEALTH & HUMAN SERVS., COMPREHENSIVE PLAN FOR ADDRESSING HIGH DRUG

PRICES: A REPORT IN REPONSES TO THE EXECUTIVE ORDER ON COMPETITION IN THE AMERICAN ECONOMY (2021),

https://aspe.hhs.gov/sites/default/files/2021-09/Drug_Pricing_Plan_9-9-2021.pdf; U.S. DEP’T OF HEALTH & HUMAN

SERVS., AMERICAN PATIENTS FIRST: THE TRUMP ADMINISTRATION BLUEPRINT TO LOWER DRUG PRICES AND REDUCE

OUT-OF-POCKET COSTS (2018), https://www.hhs.gov/sites/default/files/AmericanPatientsFirst.pdf.

2 For an examination of some of these proposals, see CRS Report R46741, Drug Pricing and Intellectual Property: The

Legislative Landscape for the 117th Congress, by Kevin J. Hickey, Kevin T. Richards, and Erin H. Ward (2021).

3 DEP’T OF HEALTH & HUMAN SERVS., OBSERVATIONS ON TRENDS IN PRESCRIPTION DRUG SPENDING 1 (Mar. 8, 2016),

https://aspe.hhs.gov/sites/default/files/pdf/187586/Drugspending.pdf; see also CRS Report R44832, Frequently Asked

Questions About Prescription Drug Pricing and Policy, by Suzanne M. Kirchhoff et al., at 3–7 (2021).

4 See generally Kirchhoff et al., supra note 3, at 21–23. For studies on this issue, see for example, GAO, PRESCRIPTION

DRUGS: U.S. PRICES FOR SELECTED BRAND DRUGS WERE HIGHER ON AVERAGE THAN PRICES IN AUSTRALIA, CANADA,

AND FRANCE (2021), https://www.gao.gov/assets/gao-21-282.pdf (finding U.S. prices for 20 brand-name prescription

drugs were two to four times higher than selected comparison countries); Andrew WQ. Mulcahy et al., International

Prescription Drug Price Comparisons, RAND CORP. (2021), https://www.rand.org/pubs/research_reports/RR2956.html

(finding U.S. drug prices in 2018 were 2.56 times higher than 32 comparison countries); OECD, HEALTH AT A GLANCE

2021, at p. 237 fig. 9.2 (finding U.S. 2019 per capita expenditures on pharmaceuticals was the highest among all

countries studied and more than twice the OECD average).

5 See generally Kirchhoff et al., supra note 3, at 3–13; Joseph Antos & James C. Capretta, Prescription Drug Pricing:

An Overview of the Legal, Regulatory and Market Environment, AM. ENTER. INST. 4–12 (2018), https://www.aei.org/

wp-content/uploads/2018/07/Prescription-Drug-Pricing.pdf; Aaron S. Kesselheim et al., The High Cost of Prescription

Drugs in the United States: Origins and Prospects for Reform, 316 JAMA: J. AM. MED. ASS’N 858, 860–63 (2016).

6 See, e.g., WILLIAM M. LANDES & RICHARD A. POSNER, THE ECONOMIC STRUCTURE OF INTELLECTUAL PROPERTY LAW

313 (2003) (citing data that new drug manufacturers are unusually “avid in seeking patent protection”); Emily Michiko

Morris, The Myth of Generic Pharmaceutical Competition under the Hatch-Waxman Act, 22 FORDHAM INTELL. PROP.

MEDIA & ENT. L.J. 245, 252 (2012) (“[P]harmaceuticals are also widely recognized as one of the industries most

dependent on patent protection to recoup its enormous research, development, regulatory, and post-marketing costs.”);

Adi Gillat, Compulsory Licensing to Regulated Licensing: Effects on the Conflict Between Innovation and Access in the

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The Role of Patents and Regulatory Exclusivities in Drug Pricing

some studies suggest that IP rights are among the most important factors driving high drug

prices.7 For example, the U.S. Food and Drug Administration (FDA) has found that increased

competition from generic drug manufacturers is associated with much lower prices for

pharmaceuticals.8

Given that IP rights can deter or delay the market entry of generic drug or biosimilar competition,

and thus may allow the rights holder to charge higher-than-competitive prices, some see changing

IP rights as a potential way to lower prices for pharmaceutical products.9 Other stakeholders are

wary of undermining IP rights, which play an important role in facilitating development of new

pharmaceutical products.10 A key focus of this debate, then, is whether existing IP law properly

balances the need for innovation with the costs that IP rights may impose on consumers and the

public.11 Understanding the interplay between several complex legal regimes is necessary to

understand this debate.

The scope and enforcement of IP rights in pharmaceutical products depends upon several

underlying legal and regulatory regimes, including FDA law, patent law, and antitrust law. In

addition to patent protection, certain pharmaceuticals, such as innovative products or those that

serve particular needs, may qualify for periods of regulatory exclusivity when they are approved

or licensed by FDA.12 FDA regulates pharmaceutical products differently if they derive from

biological, as opposed to chemical, sources. In particular, under the Federal Food, Drug, and

Cosmetic Act (FD&C Act), FDA must approve nonbiological “drugs” before they can be

marketed or sold,13 whereas “biologics”14 must be licensed by FDA under the Public Health

Service Act (PHSA).15

This regulatory distinction has patent law consequences because patents on pharmaceutical drugs

or biologics are subject to different specialized patent dispute resolution procedures, which can

affect another manufacturer’s ability to bring a generic drug or biosimilar version of an existing

product to market. Provisions of the Drug Price Competition and Patent Term Restoration Act of

Pharmaceutical Industry, 58 FOOD & DRUG L.J. 711, 722 (reviewing data “supporting relatively high dependency of

the pharmaceutical industry on patent rights”).

7 See, e.g., Kesselheim et al., supra note 5, at 861 (“The most important factor that allows manufacturers to set high

drug prices for brand-name drugs is market exclusivity, which arises from 2 forms of legal protection against

competition [i.e., regulatory exclusivities and patent rights.]”); Generic Competition and Drug Prices, FOOD & DRUG

ADMIN. (Sept. 12, 2022), https://www.fda.gov/about-fda/center-drug-evaluation-and-research-cder/genericcompetition-and-drug-prices (finding association between generic competition and lower drug prices).

8 See Generic Competition and Drug Prices, supra note 7 (showing sharp price decreases associated with the number

of generic producers of a drug).

9 See, e.g., Robin Feldman & Evan Frondorf, Drug Wars: A New Generation of Generic Pharmaceutical Delay, 53

HARV. J. ON LEGIS. 499, 556–61 (2016) (urging “comprehensive overhaul” of pharmaceutical patent laws to curtail

strategies used by pharmaceutical companies to avoid competition and maintain monopoly pricing); Kesselheim et al.,

supra note 5, at 864 (proposing limits on secondary patents and increased policing of pay-for-delay patent settlements

as possible means to curtail high drug prices).

10 See Henry G. Grabowski et al., The Roles of Patents and Research and Development Incentives in

Biopharmaceutical Innovation, 34 HEALTH AFFS. 302, 302 (2015) (“Patents and other forms of intellectual property

protection are generally thought to play essential roles in encouraging innovation in biopharmaceuticals.”).

11 See infra notes 34–43 (discussing economic rationale for IP and the costs and benefits that it may impose on the

public).

12 See infra “Regulatory Exclusivities.”

13 Under the FD&C Act, a “drug” means, among other things, an article that is “intended for use in the diagnosis, cure,

mitigation, treatment, or prevention of disease in man or other animals.” 21 U.S.C. § 321(g)(1).

14 Under the PHSA, a “biological product” or “biologic” is a medical product derived from natural sources (human,

animal, microorganism) and applicable to the prevention, treatment, or cure of disease. 42 U.S.C. § 262(i)(1).

15 See infra “FDA Approval and Licensure of Pharmaceutical Products.”

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1984 (the Hatch-Waxman Act)16 govern FDA approval and patent disputes for generic drugs,

whereas the Biologics Price Competition and Innovation Act of 2009 (BPCIA)17 governs FDA

licensure and patent disputes for biosimilars.

Given these complexities, a fair amount of legal background is necessary to understand how drug

manufacturers obtain and enforce IP rights in pharmaceuticals and how IP rights may impact drug

prices. This report provides this background, proceeding in five parts. First, it provides an

overview of the economic rationale for intellectual property in the pharmaceutical context and IP

law’s fundamental policy tradeoff between providing incentives for innovation without unduly

increasing prices for consumers. Second, the report overviews FDA requirements for obtaining

approval to market a drug or biological product, the abbreviated pathways for generic drug

approval under the Hatch-Waxman Act and biosimilar licensure under the BPCIA, and different

regulatory exclusivities that FDA grants to certain approved pharmaceutical products.18 Third, it

reviews patent law, including the requirements for obtaining a patent, the rights granted to patent

holders, and various limitations on those rights.19 Fourth, the report describes and compares the

different specialized patent dispute procedures for generic drugs and biosimilars under the HatchWaxman Act and the BPCIA, respectively.20 Finally, it overviews antitrust law and describes its

application to several patenting practices used by pharmaceutical companies to enforce their IP

rights, and overviews the debates between various stakeholders over such practices.21

IP Rights in Pharmaceuticals: Incentives for

Innovation Versus Cost and Access

In general, IP law comprises a set of exclusive rights that prevent others from making, copying, or

using certain intangible creations of the human mind.22 Federal law provides legal protection for

several different varieties of IP.23 Each form of IP covers a different type of intellectual creation,

has a different procedure for obtaining rights, and grants the IP owner legal rights that vary in

scope and duration.24

New pharmaceutical products generally benefit from two primary forms25 of IP protection: patent

rights and regulatory exclusivities.26 These two sets of exclusive rights are distinct, yet often

16 Pub. L. No. 98-417, 98 Stat. 1585 (1984) (codified as amended in relevant part at 21 U.S.C. § 355 and 35 U.S.C.

§§ 156, 271(e)).

17 Pub. L. No. 111-148, tit. VII, 124 Stat. 199, 804–21 (2010) (codified as amended in relevant part at 42 U.S.C. § 262

and 35 U.S.C. § 271(e)).

18 See infra “FDA Approval and Licensure of Pharmaceutical Products.”

19 See infra “Securing and Enforcing Patent Protections for Pharmaceuticals.”

20 See infra “Patent Dispute Procedures for Generic Drugs and Biosimilars.”

21 See infra “Pharmaceutical Patenting Practices.”

22 Cf. Intellectual Property, BLACK’S LAW DICTIONARY (10th ed. 2014) (“A category of intangible rights protecting

commercially valuable products of the human intellect.”).

23 See generally CRS In Focus IF10986, Intellectual Property Law: A Brief Introduction, by Kevin J. Hickey (2022).

24 See id.

25 Although patents and regulatory exclusivities are the most important forms of IP rights for pharmaceuticals, drugs

and biologics may be subject to other varieties of IP. For example, the brand name of a new drug is typically

trademarked, which prevents other manufacturers from using the same (or a similar) name in a way that would confuse

consumers about the source of goods or services. See 15 U.S.C. § 1114(1); see generally CRS In Focus IF12456, An

Introduction to Trademark Law in the United States, by Christopher T. Zirpoli (2023).

26 Although not a traditional form of IP such as a copyright or patent, regulatory exclusivities share many of the

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The Role of Patents and Regulatory Exclusivities in Drug Pricing

confused. In overlapping ways, both patent rights and regulatory exclusivities can operate to

prevent or delay the market entry of a generic drug or biosimilar version of a brand-name drug or

biologic.

Patents, which are available to many technologies beyond pharmaceuticals,27 are granted by the

U.S. Patent and Trademark Office (PTO) for inventions that are new, useful, nonobvious,

and directed at patentable subject matter.28 The holder of a valid patent generally has the

exclusive right to make, use, sell, or import a patented invention within the United States for a

period beginning when the PTO issues the patent and ending twenty years after the filing date of

the patent application.29

Regulatory exclusivities are granted to qualifying pharmaceutical products upon being approved

or licensed for marketing by FDA.30 Only certain pharmaceutical products, such as innovative

products (e.g., a new active ingredient or new indication for an existing drug) or those that serve a

specific need (e.g., treating rare diseases), receive such exclusivities.31 Regulatory exclusivities

generally prevent FDA from accepting or approving an application for a follow-on product (i.e., a

generic or biosimilar version) of a previously approved pharmaceutical that relies on safety and

efficacy data submitted by the original manufacturer for a period of time.32 Depending on the type

of pharmaceutical product and other factors, regulatory exclusivities may last anywhere from six

months to twelve years.33

Although each of these forms of IP is legally distinct, they broadly share a common motivation:

encouraging innovation.34 Patents are typically justified by a utilitarian rationale that exclusive

features of traditional IP rights and thus are often characterized as a form of IP. See, e.g., John R. Thomas, The End of

“Patent Medicines”? Thoughts on the Rise of Regulatory Exclusivities, 70 FOOD & DRUG L.J. 39, 43 (2015) (describing

regulatory exclusivities as “FDA-administered intellectual property rights”); Rebecca S. Eisenberg, The Role of the

FDA in Innovation Policy, 13 MICH. TELECOMM. & TECH. L. REV. 345, 359 (2007) (describing FDA regulatory

exclusivities as “pseudo-patents”). Regulatory exclusivities are analogous to patent rights because they confer a limited

monopoly on the exclusivity holder to provide an incentive for drug manufacturers to undertake the investments

necessary to complete the FDA regulatory process. See Maxwell R. Morgan, Regulation of Innovation under Follow-on

Biologics Legislation: FDA Exclusivity As an Efficient Incentive Mechanism, 11 COLUM. SCI. & TECH. L. REV. 93, 98

(2010) (“Like patent law, an FDA-administered exclusivity period can effectively confer a monopoly on a market

entrant, and thereby act as an incentive mechanism for firms to invest in the generation and clinical development of

new medicines, and also in commercializing them.”).

27 In general, a patent may be granted on any “new and useful process, machine, manufacture, or composition of matter,

or any new and useful improvement thereof.” 35 U.S.C. § 101. However, “laws of nature, natural phenomena, and

abstract ideas are not patentable.” Alice Corp. v. CLS Bank Int’l, 573 U.S. 208, 216 (2014) (quoting Ass’n for

Molecular Pathology v. Myriad Genetics, Inc., 569 U.S. 576, 589 (2013)); see generally CRS Report R45918, PatentEligible Subject Matter Reform: Background and Issues for Congress, by Kevin J. Hickey (2022).

28 See 35 U.S.C. §§ 101-103, 131. Patent applications must also conform to a number of requirements related to the

sufficiency of the technical disclosure in the patent itself. Id. § 112; see generally CRS Report R46525, Patent Law: A

Handbook for Congress, coordinated by Kevin J. Hickey (2020), at 8–17 (reviewing patentability requirements).

29 35 U.S.C. §§ 154(a)(2), 271(a).

30 See infra “FDA Approval and Licensure of Pharmaceutical Products.”

31 See infra “Regulatory Exclusivities”; see generally CRS In Focus IF11217, Drug Pricing and the Law: Regulatory

Exclusivities, by Erin H. Ward (2019).

32 Ward, supra note 31.

33 Id.

34 An exception is trademark law, which is usually justified by a different rationale: protecting consumers from

confusion and lowering product search costs by preventing businesses from misrepresenting the source of goods or

services. See Qualitex Co. v. Jacobson Prods. Co., 514 U.S. 159, 163–64 (1995). Many alternative rationales for IP

rights exist in addition to the incentives-for-creation theory. See, e.g., Justin Hughes, The Philosophy of Intellectual

Property, 77 GEO. L.J. 287, 296–314 (1988) (articulating justification for intellectual property as natural right deriving

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rights are necessary to provide incentives to produce new creative works and technological

inventions.35 This rationale maintains that absent legal protections, competitors could freely copy

such creations, denying the original creators the ability to recoup their investments in time and

effort, thereby reducing the incentive to create in the first place.36 IP incentives are said to be

particularly necessary for products, such as pharmaceuticals, that are costly to develop but easily

copied once marketed.37 In the words of the Supreme Court, IP rights are premised on an

“economic philosophy” that the “encouragement of individual effort by personal gain is the best

way to advance public welfare through the talents of authors and inventors.”38 From this

perspective, the fundamental aim of IP law is to find the optimal balance between providing

incentives for innovation and the costs that IP rights impose on the public.39 Regulatory

exclusivities, too, ideally seek to balance encouraging innovation and encouraging competition.40

By design, IP rights may lead to increased prices for IP-protected goods or services. IP rights are

often said to grant a temporary “monopoly” to the rights holder.41 The existence of a patent on a

particular manufacturing process, for example, generally means that only the patent holder (and

persons licensed by the patent holder) can use that patented process until the patent expires.42 In

from the author’s labor); id. at 330–39 (articulating justification for intellectual property as rooted in notions of

personhood); Colleen V. Chien, Contextualizing Patent Disclosure, 69 VAND. L. REV. 1849, 1850–51 (2016)

(overviewing justification for patent system as an incentive to encourage innovators to disclose technical information to

public).

35 See Sony Corp. of Am. v. Universal City Studios, Inc., 464 U.S. 417, 429 (1984) (“[Copyrights and patents are]

intended to motivate the creative activity of authors and inventors by the provision of a special reward, and to allow the

public access to the products of their genius after the limited period of exclusive control has expired.”); Twentieth

Century Music Corp. v. Aiken, 422 U.S. 151, 156 (1975) (“The immediate effect of our copyright law is to secure a fair

return for an ‘author’s’ creative labor. But the ultimate aim is, by this incentive, to stimulate artistic creativity for the

general public good.”).

36 See Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470, 480 (1974) (“The patent laws promote [the progress of the

useful arts] by offering a right of exclusion for a limited period as an incentive to inventors to risk the often enormous

costs in terms of time, research, and development.”).

37 See Grabowski et al., supra note 10, at 302 (“[T]he process of developing a new drug and bringing it to market is

long, costly, and risky, and the costs of imitation are low. After a new drug has been approved and is being marketed,

its patents protect it from competition from chemically identical entrants (or entrants infringing on other patents) for a

period of time.”); LANDES & POSNER, supra note 6, at 24 (“If the fixed costs of intellectual property—the costs incurred

before a single sale is made—are very high and . . . the costs of duplication are slight, then in the absence of intellectual

property rights either the intellectual property will not be created or the government will have to finance it . . . .”); id. at

317 (“In the case of new drugs . . . the fixed costs of research and development are very high, in part because of

stringent regulatory requirements, but the marginal costs [of imitators] are very low.”).

38 Mazer v. Stein, 347 U.S. 201, 219 (1954).

39 See Sony, 464 U.S. at 429 (“[D]efining the scope of [patents and copyrights] involves a difficult balance between the

interests of authors and inventors in the control and exploitation of their writings and discoveries on the one hand, and

society’s competing interest in the free flow of ideas, information, and commerce on the other hand. . . . ”); Mark A.

Lemley, Property, Intellectual Property, and Free Riding, 83 TEX. L. REV. 1031, 1031 (2005) (“[Traditionally,] the

proper goal of intellectual property law is to give as little protection as possible consistent with encouraging

innovation.”).

40 See infra notes 110–112 and accompanying text.

41 See, e.g., Festo Corp. v. Shoketsu Kinzoku Kogyo Kabushiki Co., 535 U.S. 722, 730 (2002) (characterizing patents

as a “temporary monopoly”); Bonito Boats, Inc. v. Thunder Craft Boats, Inc., 489 U.S. 141, 147 (1989) (characterizing

patents as a “limited monopoly”); Sony, 464 U.S. at 442 (characterizing copyright as a “statutory monopoly”). Notably,

this usage of “monopoly” is somewhat imprecise, because the exclusive rights provided by IP law do not necessarily

confer monopolistic market power in the economic sense; for example, there may be noninfringing substitutes for a

patented good in the relevant market. See LANDES & POSNER, supra note 6, at 22 (“[IP] protection creates a monopoly,

in the literal sense in which a person has a monopoly in the house he owns but [only] occasionally in a meaningful

economic sense as well because there may be no good substitutes for a particular intellectual work.”).

42 35 U.S.C. §§ 154, 271.

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some circumstances, this legal exclusivity may allow the patent holder (or her licensees) to

charge higher-than-competitive prices for goods made with the patented process, as a monopolist

would, because the patent effectively shields the patent holder from competition.43

As a result, a patent holder, such as a drug manufacturer, may have an incentive to prolong the

period of exclusivity, such as by filing for additional patents to cover a product.44 In the

pharmaceutical context, critics argue that some brand-name drug and biological product

manufacturers (the brands) use patenting strategies to “game[] the patent system” to maximize

profits and forestall competition from generic drug or biosimilar manufacturers (the generics).45

Others contend that these practices are a legitimate use of the patent system and are necessary to

incentivize the billions of dollars in R&D that lead to new, life-saving drugs.46 As these

pharmaceutical patenting practices may affect drug prices, they have attracted congressional

interest. Several legislative proposals seek to curtail these patenting practices by reducing their

effectiveness or outlawing them entirely.47 Proponents see such legislation as a potential way to

lower pharmaceutical prices.48 Later sections of this report discuss four such alleged patenting

practices: “evergreening,” “product hopping,” “patent thickets,” and “pay-for-delay”

settlements.49

FDA Approval and Licensure of Pharmaceutical

Products

The FD&C Act generally promotes public health by protecting consumers from pharmaceuticals

that are adulterated, misbranded, unsafe, or ineffective.50 To this end, new drugs and biologics

cannot be marketed in the United States without FDA approval.51 FDA law also balances

encouraging advancements in medicine through innovation against the benefits of competition,

43 See LANDES & POSNER, supra note 6, at 299–300; FTC v. Actavis, Inc., 570 U.S. 136, 147 (2013) (“[Patent rights]

may permit the patent owner to charge a higher-than-competitive price for the patented product.”).

44 See infra “Pharmaceutical Patenting Practices.”

45 See, e.g. Press Release, Office of Sen. Dick Durbin, Durbin, Cassidy Introduce REMEDY Act To Lower Drug Prices

By Curbing Patent Manipulation, Promoting Generic Competition (Apr. 11, 2019), https://www.durbin.senate.gov/

newsroom/press-releases/durbin-cassidy-introduce-remedy-act-to-lower-drug-prices-by-curbing-patent-manipulationpromoting-generic-competition (“Americans are facing skyrocketing prescription drug costs in part because brandname pharma manufacturers have gamed the patent system to extend their monopolies and avoid competition from

lower-cost generic drugs.”) (quoting Sen. Durbin); Press Release, Office of Sen. John Cornyn, Cornyn, Blumenthal

Introduce Bill to Prevent Drug Companies from Abusing Patent System (May 9, 2019) (“Drug companies have taken

advantage of the patent system to maintain their monopoly on certain drugs and prevent generics from coming to

market.”) (quoting Sen. Cornyn).

46 See, e.g., infra notes 394–416 and accompanying text.

47 See generally Hickey et al., supra note 2.

48 See, e.g., Feldman & Frondorf, supra note 9, at 556–61 (urging “comprehensive overhaul” of pharmaceutical patent

laws to curtail strategies pharmaceutical companies allegedly use to avoid competition and maintain monopoly

pricing); Kesselheim et al., supra note 5, at 864 (proposing limits on secondary patents and increased policing of payfor-delay patent settlements as possible means to curtail high drug prices).

49 See infra “Pharmaceutical Patenting Practices.”

50 See generally Wallace F. Janssen, The Story of the Laws Behind the Labels, FOOD & DRUG ADMIN. (1981),

https://www.fda.gov/downloads/aboutfda/history/forgshistory/evolvingpowers/ucm593437.pdf.

51 21 U.S.C. § 355(a); 42 U.S.C. § 262(a)(1).

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similar to patent law.52 To that end, federal law provides certain regulatory exclusivities—

generally awarded upon approval—for pharmaceutical products that meet the requisite criteria.53

FDA determines which drugs and biologics may be marketed in the United States through similar

but distinct approval processes.54 This section first overviews the approval processes for new and

generic drugs, and then discusses the processes for new and follow-on biologics. It also describes

the exclusivities Congress has created to encourage research and development of new

pharmaceutical products as well as competition from follow-on products.

New and Generic Drug Approval

Drugs are articles—generally chemical compounds—“intended for use in the diagnosis, cure,

mitigation, treatment, or prevention of disease” or “intended to affect the structure or any function

of the body.”55 New drugs, as the term is used in the FD&C Act, are those drugs that scientific

experts do not generally recognize as safe and effective for their intended use.56 A new drug may

contain an active ingredient that FDA has not previously approved, or may contain a previously

approved active ingredient with the drug modified in one or more other aspects from the

approved drug, such as the indication, patient population, formulation, strength, dosage form, or

route of administration. All new drugs require FDA approval before they are marketed in the

United States.57

New Drug Approval

New drugs are approved through the new drug application (NDA) process. To obtain approval for

a new drug, a sponsor must conduct “costly and time-consuming studies,”58 including clinical

trials, demonstrating the drug’s safety59 and effectiveness60 for humans.61 Clinical trials,

conducted after the company has completed basic research and nonclinical testing, assess the

safety, efficacy, and effectiveness of the drug in volunteer human subjects under carefully

controlled conditions.62 When the company is ready to begin clinical trials, it submits an

52 See, e.g., King Drug Co. of Florence, Inc. v. Smithkline Beecham Corp., 791 F.3d 388, 394 (3d Cir. 2015)

(“Congress attempted to balance the goal of ‘mak[ing] available more low cost generic drugs, H.R. Rep. No. 98-857,

pt. 1, at 14–15 (1984), reprinted in 1984 U.S.C.C.A.N. 2647, 2647–48, with the value of patent monopolies in

incentivizing beneficial pharmaceutical advancement, see H.R. Rep. No. 98-857, pt. 2, at 30 (1984), reprinted in 1984

U.S.C.C.A.N. 2686, 2714.”); Yaniv Heled, Patents v. Statutory Exclusivities in Biological Pharmaceuticals—Do We

Really Need Both?, 18 MICH. TELECOMM. & TECH. L. REV. 419, 427–30, 434–36 (2012).

53 See infra “Regulatory Exclusivities.”

54 See generally 21 U.S.C. § 355; 42 U.S.C. § 262.

55 21 U.S.C. § 321(g).

56 Id. § 321(p).

57 Id. § 355(a).

58 FTC v. Actavis, 570 U.S. 136, 142 (2013).

59 “Safety” in the FDA context is measured by the number and seriousness of adverse events and reactions in persons

exposed to the drug. See, e.g., 21 C.F.R. § 312.32 (2023).

60 “Efficacy” refers to whether the drug performs better than a placebo under controlled conditions. See generally Amit

Singal, Peter Higgins & Akbar Waljee, A Primer on Effectiveness and Efficacy Trials, 5(1) J. CLINICAL &

TRANSLATIONAL GASTROENTEROLOGY e45 (2014), https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3912314/.

Effectiveness examines how the drug performs under real-world conditions where it may not be prescribed or taken as

intended or may interact with other drugs or health conditions. Id.

61 21 C.F.R. § 314.50(d)(5).

62 21 U.S.C. §355(i); 21 C.F.R. § 312.21. As amended by the Consolidated Appropriations Act, 2023, the FD&C Act

(continued...)

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investigational new drug (IND) application to FDA.63 The IND application provides FDA with

information about the drug as well as a proposed clinical study design that has been reviewed and

approved by an Institutional Review Board (IRB).64 Unless FDA objects within 30 days of

receiving the IND application, clinical investigations may proceed.65

Clinical testing occurs in three phases.66 Phase I clinical trials generally test the drug in a small

number of subjects and focus on evaluating the drug’s safety.67 During Phase I clinical trials, the

sponsor evaluates how the drug is processed (metabolized and excreted) in the body, determines

the highest tolerable dose and optimal dose of the drug, and identifies any acute adverse side

effects of the drug.68 Phase II and Phase III clinical trials evaluate the drug’s efficacy in addition

to continuing to evaluate safety.69 These trials generally use a larger group of test subjects who

have the characteristic, condition, or disease the drug treats.70 Phase II studies generally are still

well-controlled and “usually involv[e] no more than several hundred subjects,” whereas Phase III

studies may include expanded controlled and uncontrolled trials and “usually include from

several hundred to several thousand subjects.”71

Once clinical trials are complete, the sponsor may submit the results to FDA’s Center for Drug

Evaluation and Research (CDER) in an NDA.72 The NDA also includes information about the

drug, proposed labeling, and planned manufacturing process.73

FDA reviews the NDA to determine whether there is “substantial evidence” that the drug is safe

and effective for the proposed use, including whether the benefits of the drug outweigh the

risks.74 Section 505(d) of the FD&C Act defines substantial evidence to mean “adequate and wellcontrolled investigations” based on which qualified scientific experts could “fairly and

responsibly” conclude that the product has the purported effect.75 FDA assesses both the quality

provides that nonclinical tests used to support evidence of a drug’s safety or effectiveness may include any in vitro, in

silico, or in chemico test, or a nonhuman in vivo test, before or during the clinical trial phase, including cell-based

assays, organ chips and microphysiological systems, computer modeling, other nonhuman or human biology-based test

methods, and animal tests. 21 U.S.C. § 355(z).

63 21 C.F.R. § 312.20.

64 Id. § 312.23.

65 Id. §§ 312.40, 312.42.

66 Id. § 312.21.

67 Id. § 312.21(a).

68 Id.

69 Id. § 312.21(b)–(c).

70 Id.

71 Id.

72 21 U.S.C. § 355(b). The FD&C Act provides for two types of NDAs in section 505(b), depending on whether the

application includes only studies to which the company has a right of reference (under 505(b)(1)) or includes studies to

which the company does not have a right of reference (e.g., published literature or FDA’s finding of safety and efficacy

for a related approved drug) (a so-called “paper NDA” under 505(b)(2)). Id.; see also U.S. FOOD & DRUG ADMIN.,

DRAFT GUIDANCE FOR INDUSTRY: APPLICATIONS COVERED BY SECTION 505(B)(2) (1999), https://www.fda.gov/

downloads/Drugs/Guidances/ucm079345.pdf.

73 21 U.S.C. § 355(b).

74 21 U.S.C. § 355(d).

75 Id.

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and quantity of the data provided when determining whether a product meets this standard.76 The

agency also reviews the proposed labeling and the manufacturing controls.77

FDA sends a letter to the drug sponsor with the agency’s determination.78 If the NDA meets the

requirements for approval, FDA sends an approval letter or, if patent rights or exclusivities bar

immediate approval, a tentative approval letter.79 FDA may impose conditions on its approval of

an NDA, such as requiring the company to conduct additional post-market clinical studies,

referred to as Phase IV clinical trials.80 If the NDA does not meet the requirements for approval,

FDA sends a complete response letter explaining the deficiencies FDA identified in the NDA and

how they might be remedied.81

Generic Drug Approval

Before the Hatch-Waxman Act was enacted in 1984, every new drug submitted to FDA for

preapproval required a complete application under Section 505(b) supported by clinical trial data

demonstrating safety and effectiveness.82 To encourage generic drug entry, the Hatch-Waxman

Act established a pathway for abbreviated new drug applications (ANDAs),83 which allows

generic manufacturers to rely on FDA’s prior approval of another drug with the same active

ingredient—the reference listed drug (RLD)—to establish that the generic drug is safe and

effective.84 The ANDA pathway allows generic manufacturers to avoid the long, expensive

process of conducting their own clinical trials.85 The generic manufacturer need only conduct

studies with its generic product and samples of the RLD to demonstrate that the generic drug is

pharmaceutically equivalent86 and bioequivalent87 to the RLD.88 The ANDA also includes the

generic manufacturer’s proposed labeling, which must be identical to the RLD’s labeling except

76 U.S. FOOD & DRUG ADMIN., DEMONSTRATING SUBSTANTIAL EVIDENCE OF EFFECTIVENESS FOR HUMAN DRUG AND

BIOLOGICAL PRODUCTS: DRAFT GUIDANCE FOR INDUSTRY 3 (Dec. 2019), https://www.fda.gov/media/133660/

download77 Id. Manufacturing information includes the manufacturer’s name and address, manufacturing methods and

process controls, and specifications to ensure a product’s integrity for both the marketed drug substance and any drug

components used to manufacture the drug. 21 C.F.R. § 314.50(d)(1).

77 Id. Manufacturing information includes the manufacturer’s name and address, manufacturing methods and process

controls, and specifications to ensure a product’s integrity for both the marketed drug substance and any drug

components used to manufacture the drug. 21 C.F.R. § 314.50(d)(1).

78 21 C.F.R. § 314.105.

79 Id.

80 Id.

81 Id. § 314.110.

82 21 U.S.C. § 355(b) (1982). FDA did permit applicants to rely on published studies to meet the “full reports of

investigations” requirement through its Paper NDA policy. See Publication of “Paper NDA” Memorandum, 46 Fed.

Reg. 27396, 27396 (May 19, 1981).

83 Drug Price Competition and Patent Term Restoration Act, Pub. L. No. 98-417, § 101, 98 Stat. 1585 (1984) (referred

to as the Hatch-Waxman Act).

84 21 C.F.R. §§ 314.92, 314.94.

85 Actavis v. FTC, 570 U.S. 136, 142 (2013).

86 Drugs are pharmaceutically equivalent if they have the same active ingredient(s), strength, dosage form, and route of

administration. 21 C.F.R. § 314.3. Other elements that do not impact safety or effectiveness, such as the drug’s inactive

ingredients, may be different. Id.

87 Bioequivalence means the drugs work the same way inside the body; that is, there is no significant difference in the

rate at which and extent to which the drug’s active ingredient reaches the place in the body where the drug is active,

when administered at the same dose and under similar conditions. Id. § 320.1(e).

88 21 U.S.C. § 355(j)(2)(A); 21 C.F.R. §§ 314.94, 320.21.

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for manufacturing information and any FDA-approved changes.89 ANDA filers submit

information on pharmaceutical equivalence and bioequivalence studies, proposed labeling, and

any patent certifications90 to FDA to obtain approval.91

Biological Product and Biosimilar Licensure

A biological product is derived from biological material, such as a virus, toxin, blood component,

or protein, and used for “the prevention, treatment, or cure of a disease or condition of human

beings.”92 Biological products “are generally large, complex molecules” that “may be produced

through biotechnology in a living system, such as a microorganism, plant cell, or animal cell.”93

“Inherent variations” between different batches of the same biological product are “normal and

expected.”94 According to FDA, the complexity and variability of biological products “can

present challenges in characterizing and manufacturing these products that often do not exist in

the development of small molecule drugs.”95 FDA’s process for approving biological products and

generic versions of previously approved products aims to account for these challenges.

Biological Products

To be marketed in the United States, a biological product must be (1) covered by a valid biologics

license and (2) marked with the product’s proper name; the manufacturer’s name, address, and

applicable license number; and the product’s expiration date.96 A biological product manufacturer

may obtain a biologics license by submitting a biologics license application (BLA) to FDA’s

Center for Biologics Evaluation and Research (CBER) or CDER for approval.97 The BLA must

include, among other things, data from nonclinical and clinical studies, information about the

manufacturing methods and locations, proposed labels and containers to be used, and (if

applicable) a proposed Medication Guide.98 FDA must also be able to examine the product and

determine that it “complies with the standards established” in the BLA and other requirements,

including good manufacturing practices.99

89 21 U.S.C. § 355(j)(2)(A)(v).

90 See infra “The Hatch-Waxman Act: Patents and Generic Drug Approval.”

91 21 U.S.C. § 355(j)(2)(A).

92 42 U.S.C. § 262(i); 21 C.F.R. § 600.3.

93 U.S. FOOD & DRUG ADMIN., BIOLOGICAL PRODUCT DEFINITIONS, https://www.fda.gov/downloads/Drugs/

DevelopmentApprovalProcess/HowDrugsareDevelopedandApproved/ApprovalApplications/

TherapeuticBiologicApplications/Biosimilars/UCM581282.pdf (last visited Jan. 26, 2024)

94 Id.

95 Id.

96 42 U.S.C. § 262(a)(1).

97 21 C.F.R. § 601.2(a). An intercenter agreement between CBER and CDER governs which center reviews a particular

product application and regulates the product if approved. Intercenter Agreement Between the Center for Drug

Evaluation and Research and the Center for Biologics Evaluation and Research, FOOD & DRUG ADMIN. (Oct. 25,

1991), https://www.fda.gov/CombinationProducts/JurisdictionalInformation/ucm121179.htm. In 2003, FDA transferred

some therapeutic biological products from CBER to CDER. See Transfer of Therapeutic Biological Products to the

Center for Drug Evaluation and Research, FOOD & DRUG ADMIN. (June 30, 2003), https://www.fda.gov/

CombinationProducts/JurisdictionalInformation/ucm136265.htm.

98 21 C.F.R. § 601.2(a). FDA requires Medication Guides for products that “pose a serious and significant public health

concern,” necessitating patient labeling to inform patients of serious adverse risks and ensure safe and effective use of

the product. Id. § 208.1. Generally, FDA requires Medication Guides for “prescription drug products used on an

outpatient basis without direct supervision by a health professional.” Id.

99 Id. § 601.20.

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To approve a BLA, FDA must determine that the biological product is “safe, pure, and potent”

and that the production and distribution process “meets standards designed to assure that the

biological product continues to be safe, pure, and potent.”100 As with drug approvals, FDA either

issues the license or issues a complete response letter detailing the reasons for denying the

license.101 After approval, BLA holders must notify FDA of any changes to “the product,

production process, quality controls, equipment, facilities, responsible personnel, or labeling.”102

Biosimilar or Interchangeable Products

As with the Hatch-Waxman Act, Congress created an abbreviated approval process for biological

products through BPCIA. Under the abbreviated process, a company can obtain a license to

market a biological product if it can demonstrate that the product is biosimilar to, or

interchangeable with, an approved biological product, referred to as the “reference product.”103

Along with its BLA for a biosimilar, the manufacturer must submit data demonstrating that its

product is “highly similar to the reference product notwithstanding minor differences in clinically

inactive components” with no “clinically meaningful differences” between the two products “in

terms of the safety, purity, and potency of the product.”104 “[T]he condition or conditions of use

prescribed, recommended, or suggested in the labeling” must have been approved for the

reference product.105 The biosimilar product must use “the same mechanism or mechanisms of

action” to treat any applicable conditions, and have the same route of administration, dosage

form, and strength as the reference product.106 Finally, the biosimilar product license application

must demonstrate that the production and distribution facilities meet “standards designed to

assure that the biological product continues to be safe, pure, and potent.”107

Along with a BLA for an interchangeable product, the manufacturer must submit data

demonstrating that the product is biosimilar to the reference product and “can be expected to

produce the same clinical result as the reference product in any given patient.”108 Additionally, for

a biological product administered to an individual more than once, the manufacturer must also

show that the product does not create a greater “risk in terms of safety or diminished efficacy”

from alternating or switching between the biosimilar product and reference product than if the

reference product was used alone.109 Interchangeable products “may be substituted for the

reference product without the intervention of the health care provider who prescribed the

reference product.”110

100 42 U.S.C. § 262(a)(2)(C). A product is safe when it is “relative[ly] free[] from harmful effect to the persons

affected, directly or indirectly, by a product when prudently administered,” accounting for the product’s nature and the

recipient’s condition. 21 C.F.R. § 600.3(p). A pure product is “relative[ly] free[] from extraneous matter in the finished

product,” regardless of whether the extraneous matter is harmful. Id. § 600.3(r). Finally, the potency of the product

depends on its “specific ability or capacity . . . to effect a given result,” as demonstrated through “appropriate

laboratory tests or by adequately controlled clinical data.” Id. § 600.3(s).

101 21 C.F.R. §§ 601.3, 601.4.

102 Id. § 601.12.

103 42 U.S.C. § 262(k).

104 Id. § 262(i)(2).

105 Id. § 262(k)(2)(A)(i)(III).

106 Id. § 262(k)(2)(A)(i)(II) & (IV).

107 Id. § 262(k)(2)(A)(i)(V).

108 Id. § 262(k)(4).

109 Id. § 262(k)(4).

110 Id. § 262(i)(3).

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Regulatory Exclusivities

To balance increasing competition—which the abbreviated approval pathways aim to facilitate—

with the countervailing interest in encouraging innovation, federal law establishes periods of

regulatory exclusivity that limit FDA’s ability to approve generic drugs and biosimilars under

certain circumstances.111 These regulatory exclusivities aim to encourage companies to incur the

expense of generating clinical data and other information needed to support an NDA or BLA for

new drugs or biological products.112 They also encourage follow-on product manufacturers to

submit abbreviated applications as soon as permissible.113

There are two general categories of regulatory exclusivity: (1) data exclusivity, which precludes

other applicants from relying on FDA’s safety and effectiveness findings for the reference product

(based on the NDA or BLA holder’s data) to demonstrate a follow-on product’s safety and

effectiveness; and (2) marketing exclusivity, which precludes FDA from approving any other

application for the same pharmaceutical product and use, regardless of whether the applicant has

generated its own safety and effectiveness data.114 During a period of data exclusivity, a company

could submit an NDA or BLA for the same pharmaceutical product and use if it conducted its

own clinical trials.115 Functionally, data exclusivity and marketing exclusivity may generate the

same result due to the investment required to generate the necessary data.

New Drugs or Biological Products

Federal law provides regulatory exclusivities for new drug and biological products that differ

based on such factors as how innovative the product is or the nature of the treatment population.

For new drugs, an NDA filer who obtains approval for a drug that contains a new chemical entity

(i.e., a new active ingredient) for which no other drug has been approved is eligible for five years

of data exclusivity running from the time of NDA approval.116 During that period, no ANDA or

505(b)(2) NDA (i.e., applications that, by definition, would reference the NDA data) containing

the same active ingredient as the RLD may be submitted to FDA.117 One exception is that after

four years, FDA may accept for review an ANDA or 505(b)(2) application for the same active

ingredient if the application contains a paragraph IV certification that a patent listed in the

111 See, e.g., King Drug Co. of Florence, Inc. v. Smithkline Beecham Corp., 791 F.3d 388, 394 (3d Cir. 2015)

(“[Through] Hatch-Waxman, Congress attempted to balance the goal of ‘mak[ing] available more low cost generic

drugs,’ with the value of patent monopolies in incentivizing beneficial pharmaceutical advancement[.]” (internal

citations omitted)); Heled, supra note 52. For a comparison of regulatory exclusivities and patent exclusivities, see

infra Table 2.

112 Heled, supra note 52, at 427–30, 440.

113 21 U.S.C. § 355(j)(5)(B)(iii), (iv); 42 U.S.C. § 262(k)(6); see also Actavis v. FTC, 570 U.S. 136, 143–44 (2013);

Heled, supra note 52, at 428–29.

114 There is no standard terminology for regulatory exclusivities. Some commentators use terms such as “data

protection” and “marketing exclusivity” synonymously with “regulatory exclusivity.” This report follows a second

approach that ascribes distinct meanings to the terms. See generally Heled, supra note 52, at 436 n.67.

115 Id.

116 21 U.S.C. § 355(c)(3)(E)(ii), (j)(5)(F)(ii); 21 C.F.R. § 314.108(b)(2).

117 This five-year new drug exclusivity, however, would not prevent FDA from accepting and approving a duplicate

version of the same drug product if the duplicate version is the subject of its own NDA with its own safety and efficacy

data. See Small Business Assistance: Frequently Asked Questions for New Drug Product Exclusivity, FOOD & DRUG

ADMIN. (Feb. 11, 2016), https://www.fda.gov/drugs/developmentapprovalprocess/smallbusinessassistance/

ucm069962.htm.

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“Orange Book”—an FDA publication that catalogs the patents associated with each approved

drug118—for the RLD is either invalid or would not be infringed by the generic drug.119

NDA or supplemental NDA (sNDA)120 sponsors who obtain approval for drugs that contain

approved chemical entities, but are sufficiently changed from the approved drug (e.g., a new

indication or formulation) to require additional clinical studies to be approved, are eligible for

three years of data exclusivity running from the time of NDA approval.121 Unlike the five-year

exclusivity for new chemical entities, FDA may accept ANDA and 505(b)(2) submissions that

reference the changes meriting exclusivity during the three-year time period.122 The three-year

exclusivity relates to when FDA may approve such applications.123 To obtain such three-year

exclusivity, the NDA or sNDA must “contain[] reports of new clinical investigations (other than

bioavailability studies)” that were “essential to the approval” of the application.124 In other words,

the sponsor must have conducted or sponsored additional clinical trials that were necessary to

obtain approval of the new drug in order to benefit from the three-year exclusivity for that new

condition. As a result, three-year exclusivity is generally limited to new drugs that are

significantly changed from approved drugs, rather than to minor modifications of those products.

For brand-name biological products, the BPCIA establishes two applicable periods of exclusivity.

First, for new biological products (i.e., reference products), no biosimilar applications can be

submitted for four years “after the date on which the reference product was first licensed.”125

Second, approval of biosimilar applications cannot become effective until twelve years “after the

date on which the reference product was first licensed.”126 Together, these exclusivity periods

mean that for the first four years after a reference biological product is licensed, FDA does not

accept any biosimilar applications for review; for the next eight years, FDA accepts biosimilar

applications for review, but it cannot approve any biosimilar application until twelve years after

the date on which the reference product was first licensed. FDA has not adopted a formal position

on whether these exclusivity periods are data or marketing exclusivity periods.127 Supplemental

118 U.S. FOOD & DRUG ADMIN., APPROVED DRUG PRODUCTS WITH THERAPEUTIC EQUIVALENCE EVALUATIONS (43 ed.

2023), https://www.fda.gov/media/71474/download [hereinafter the “Orange Book”]; see also

https://www.accessdata.fda.gov/scripts/cder/ob/index.cfm (searchable version of the Orange Book).

119 21 U.S.C. § 355(c)(3)(E)(ii), (j)(5)(F)(ii); 21 C.F.R. § 314.108(b)(3). For more information on paragraph IV

certifications, see infra “The Hatch-Waxman Act: Patents and Generic Drug Approval.”

120 Under FDA regulations, changes to a drug’s label, dosage, strength, or manufacturing methods require an sNDA. 21

C.F.R. § 314.70. sNDAs must include post-market information such as commercial marketing experience and reports in

scientific literature, in addition to descriptions and analyses of clinical studies. Id. § 314.50(d)(5)(iv). sNDA sponsors

are only eligible for three-year exclusivity because sNDAs amend existing NDAs with approved chemical entities. Id.

§ 314.108(b).

121 21 U.S.C. § 355(c)(3)(E)(iii)–(iv), (j)(5)(F)(iii)–(iv).

122 Compare id. with id. § 355(c)(3)(E)(ii), (j)(5)(F)(ii).

123 Id. § 355(c)(3)(E)(iii)–(iv), (j)(5)(F)(iii)–(iv).

124 Id.

125 42 U.S.C. § 262(k)(7)(B).

126 Id. § 262(k)(7)(A).

127 This issue has been the subject of discussions between FDA and some lawmakers. See Letter from Rep. Anna G.

Eshoo et al., to FDA (Dec. 21, 2010), http://patentdocs.typepad.com/files/letter-to-fda.pdf (signed by Reps. Barton,

Eshoo, and Inslee); Letter from Sen. Sherrod Brown et al., to Dr. Margaret Hamburg, Comm’r, FDA (Jan. 24, 2011),

http://patentdocs.typepad.com/files/senator-letters-exclusivity.pdf (signed by Sens. Brown, Harkin, McCain, and

Schumer). If the exclusivity periods are marketing exclusivities, they would more broadly prevent even an application

supported by its own, full clinical trial data from being approved during the 12-year period. More recently, FDA issued

guidance that describes the exclusivity periods as limiting approval of an application “referencing [the reference]

product,” which indicates FDA may consider the exclusivity periods to provide only data exclusivity. U.S. FOOD &

(continued...)

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BLAs, for example to change the “indication, route of administration, dosing schedule, dosage

form, delivery system, delivery device, or strength,” are not eligible for these four- and twelveyear regulatory exclusivity periods.128

Generic Drug and Biosimilar Exclusivities

In addition to providing incentives for innovation, regulatory exclusivities are also used to

promote competition by encouraging the entry of follow-on products. When an RLD has one or

more patents listed in the Orange Book that have not expired, potential ANDA applicants have

two choices: (1) wait until all listed patents have expired to apply for approval or (2) file a

paragraph IV certification129 asserting that any active patents are invalid or would not be infringed

by the generic product.130 The potential for ensuing patent litigation raises the anticipated costs

for the first ANDA filer with a paragraph IV certification, as compared to subsequent ANDA

filers.131 Accordingly, to incentivize generic manufacturers to be the first filer and to challenge

listed patents purportedly covering an RLD, the Hatch-Waxman Act provides a 180-day

exclusivity to the first ANDA applicant who successfully challenges an unexpired patent listed for

the RLD using a paragraph IV certification, either by the RLD manufacturer declining to initiate

litigation within forty-five days of receiving notice from the ANDA applicant of the paragraph IV

certification or by obtaining a settlement or court ruling finding the challenged patent is invalid or

not infringed.132 This exclusivity period precludes FDA from approving another ANDA for the

same RLD during the 180-day period after the first commercial marketing of the generic drug.133

180-day exclusivity may be forfeited for a number of reasons, such as failing to commercially

market the drug within a certain timeframe.134

The BPCIA similarly awards regulatory exclusivity to the first interchangeable biological product

for a particular reference product.135 This exclusivity precludes FDA from making an

interchangeability determination for a subsequent biologic relying on the same reference product

for any condition of use until such exclusivity expires, the timing of which depends on the status

of a relevant patent dispute.136 Specifically, the exclusivity period ends at the earlier of

•

•

•

one year after the commercial marketing of the first interchangeable product;

eighteen months after a final court decision in a patent infringement action

against the first applicant or the dismissal of such an action;

forty-two months after approval if the first applicant has been sued and the

litigation is still ongoing; or

DRUG ADMIN., INTERPRETATION OF THE “DEEMED TO BE A LICENSE” PROVISION OF THE BIOLOGICS PRICE COMPETITION

AND INNOVATION ACT OF 2009: GUIDANCE FOR INDUSTRY 3 (2018), https://www.fda.gov/ucm/groups/fdagov-public/

@fdagov-drugs-gen/documents/document/ucm490264.pdf.

128 42 U.S.C. § 262(k)(7)(C).

129 ANDA applicants must provide one of four certifications for each listed patent for the RLD. 21 U.S.C.

§ 355(j)(2)(vii). Paragraph IV certifications assert that the listed patent has not expired but is invalid or will not be

infringed by the generic product. Id. § 355(j)(2)(vii)(IV); see also infra “The Hatch-Waxman Act: Patents and Generic

Drug Approval.”

130 See infra “Patent Dispute Procedures for Generic Drugs and Biosimilars.”

131 Id.

132 21 U.S.C. § 355(j)(5)(B)(iv), (j)(5)(D)(iii)(II).

133 Id. § 355(j)(5)(B)(iv).

134 Id. § 355(j)(5)(D).

135 42 U.S.C. § 262(k)(6).

136 Id.

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•

eighteen months after approval if the first applicant has not been sued.137

Other Regulatory Exclusivities

There are also a number of regulatory exclusivities aimed at encouraging entry into markets that

serve smaller or underserved populations or have limited competition. For example, Congress

passed the Orphan Drug Act in 1983 to encourage development of drugs and biologics to treat

rare diseases and conditions, called “orphan drugs.”138 Because these drugs often treat small

patient populations, and thus may provide fewer financial incentives for pharmaceutical

manufacturers to develop them, the law (among other measures) provides a seven-year marketing

exclusivity for companies that obtain approval for these drugs.139 During the seven-year period,

FDA cannot approve an NDA or BLA for the same drug or biologic to treat the same disease or

condition, even if the second applicant generates its own safety and efficacy data.140

To receive the orphan-drug exclusivity, (1) the drug must be intended to treat a “rare disease or

condition,”141 and (2) FDA must not have previously approved the same drug “for the same use or

indication.”142 To meet the first condition, a sponsor may request, before submitting an NDA or

BLA, that FDA designate its drug as one for a rare disease or condition.143 To designate an orphan

drug, FDA must determine—when the designation is requested—the disease or condition the drug

will treat “(A) affects less than 200,000 persons in the United States or (B) affects more than

200,000 in the United States and for which there is no reasonable expectation than the cost of

developing and making available in the United States a drug for such disease or condition will be

recovered from sales in the United States of such drug.”144 Drugs so designated are entitled to the

seven-year exclusivity if they also meet the second condition.

In addition, the FD&C Act provides a 180-day exclusivity to ANDAs for drugs designated by

FDA (pursuant to the ANDA filer’s request) as a “competitive generic therapy” (CGT) due to

“inadequate generic competition.”145 To receive the exclusivity, the ANDA must be the first filed

for the CGT.146 The ANDA must also have been submitted when there were “no unexpired patents

137 Id.

138 Pub. L. No. 97-414, § 1, 96 Stat. 2049 (1983) (codified as amended at 21 U.S.C. §§ 360aa–360ff-1)

139 21 U.S.C. § 360cc(a).

140 Id. § 360cc. This exclusivity is subject to two exceptions: (1) if the exclusivity holder “cannot ensure the availability

of sufficient quantities of the drug to meet the needs of persons with the disease or condition for which the drug was

designated”; and (2) if the NDA or BLA holder consents to the approval of another application for the same drug. Id.

§ 360cc(b).

141 Id. §§ 360bb, 360cc.

142 Id. § 360cc; 21 C.F.R. § 316.3(b)(12). However, an NDA or BLA filer may receive exclusivity for an alreadyapproved drug designated for the same rare disease or condition if it can demonstrate clinical superiority. 21 U.S.C.

§ 360cc(c).

143 An orphan drug is one that treats a “rare disease or condition” that either (1) “affects less than 200,000 persons in

the United States” or (2) “affects more than 200,000 persons in the United States and for which there is no reasonable

expectation that the cost of developing and making available in the United States a drug for such disease or condition

will be recovered from sales in the United States of such drug.” Id. § 360bb(a)(2).

144 Id.

145 Id. § 356h(b).

146 Id. § 355(j)(5)(B)(v).

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or exclusivities listed in the Orange Book for the relevant RLD.”147 Finally, the applicant must

commercially market the drug within seventy-five days of approval.148

To encourage manufacturers to evaluate the safety and effectiveness of their pharmaceutical

products for children, NDA and BLA filers may obtain a pediatric exclusivity if FDA determines

the drug or biological product “may produce health benefits” in the pediatric population and the

filer completes pediatric studies at FDA’s request.149 Pediatric exclusivity adds six months to any

existing exclusivity the NDA or BLA filer has obtained.150 For example, if the NDA filer obtains

a five-year exclusivity for a new active ingredient and conducts the requested pediatric studies, it

is entitled to five and a half years of exclusivity.151

Table 1. Regulatory Exclusivities for Pharmaceutical Products

Type of

Exclusivity

Length

Criteria

Effect

New Chemical

Entity

21 U.S.C.

§ 355(c)(3)(E)(ii),

(j)(5)(F)(ii), (u)

5 years

(4 years if

ANDA contains

a paragraph IV

certification)

Application for drug containing an active

moiety that has never been approved; or

application for a drug that contains as an

active ingredient a single enantiomer (each

of a pair of molecules that are mirror

images of one another) of a previously

approved racemic drug (a mixture of both

enantiomers) that treats a different

therapeutic category and does not rely on

the racemic drug’s data

FDA cannot accept an

abbreviated application

for the same active

moiety that relies on

the data in the

reference drug

application

New Clinical

Investigation

21 U.S.C.

§ 355(c)(3)(E)(iii)–

(iv), (j)(5)(F)(iii)–(iv)

3 years

Application for a change to an approved

drug that contains at least one new clinical

investigation that is “essential to the

approval” of the application and is

conducted or sponsored by the applicant

FDA cannot approve

an application that

relies on the data in

the reference drug

application for 3 years

First to File

Paragraph IV

Certification

21 U.S.C.

§ 355(j)(5)(B)(iv)

180 days

First to file an ANDA with a paragraph IV

certification that a patent listed for the

reference drug is invalid or not infringed by

the generic product

FDA cannot approve

an ANDA for the same

drug until 180 days

after first commercial

marketing of first filer

Competitive

Generic Therapy

21 U.S.C.

§§ 355(j)(5)(B)(v),

356h(b)

180 days

Designation as competitive generic therapy

by FDA based on finding of “inadequate

generic competition” (only one active

approved drug);

No unexpired patents or exclusivities for

reference product

Once first approved

applicant commences

commercial marketing,

FDA cannot approve

an ANDA for the same

reference product for

180 days after first

commercial marketing

Drugs

Biologics

147 U.S. FOOD & DRUG ADMIN., COMPETITIVE GENERIC THERAPIES (2019), https://www.fda.gov/ucm/groups/fdagov-

public/@fdagov-drugs-gen/documents/document/ucm631401.pdf.

148 21 U.S.C. § 355(j)(5)(B)(v), (j)(5)(D)(iv); COMPETITIVE GENERIC THERAPIES, supra note 147, at 18.

149 21 U.S.C. § 355a(b)–(c); 42 U.S.C. § 262(m).

150 21 U.S.C. § 355a(b)–(c); 42 U.S.C. § 262(m).

151 21 U.S.C. § 355a(b)–(c).

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Type of

Exclusivity

Biologic

Reference

Product

42 U.S.C.

§ 262(k)(7)(A), (B)

Length

Criteria

Effect

4 years

(application)

and 12 years

(approval) after

date of first

licensure

First licensure of a biological product that is:

FDA cannot accept an

abbreviated BLA

referencing the

product for first 4

years;

FDA cannot approve

an abbreviated BLA

referencing the

product for 12 years

1. Not a supplemental application;

2. Not a change resulting in a new

indication, route of administration, dosing

schedule, dosage form, delivery system,

delivery device, or strength; and

3. Not a modification to structure of

product that does not result in a change in

safety, purity, or potency

Interchangeable

Biologic

42 U.S.C. § 262(k)(6)

12–42 months

(see Effects

column)

First interchangeable biologic approved for a

reference product;

Interchangeable means the product is

biosimilar to the reference product,

produces the same clinical result in any

given patient, and a patient can switch

between the interchangeable and reference

products over multiple doses without

altering risk

FDA cannot determine

another product is

interchangeable with

the reference product

for any condition of

use until the earliest of:

(1) 1 year after

commercial marketing;

(2) 18 months after

approval if not sued; or

(3) if sued, 18 months

after decision or 42

months after approval

Pediatric Studies

21 U.S.C. § 355a(b),

(c)

42 U.S.C. § 262(m)

6 months

FDA requests that applicant conducts

pediatric studies and such studies are

completed

Extends other

exclusivities by 6

months;

Delays approval for 6

months after listed

patents expire

Orphan Drug

21 U.S.C. § 360cc

7 years

FDA designation as an orphan drug: a drug

that treats a disease or condition that affects

less than 200,000 people in the United

States, or affects more than 200,000 people

in the United States but there is no

reasonable expectation that the cost of

developing and making the drug would be

recovered

FDA cannot approve

another application for

the same drug for the

same disease or

condition for 7 years,

with limited exceptions

Qualified

Infectious Disease

Product

21 U.S.C. § 355f

5 years

FDA designation as a qualified infectious

disease product (QIDP): an antibacterial or

antifungal drug intended to treat serious or

life-threatening infections, including those

caused by qualifying or resistant pathogens

Extends other

exclusivities by 5 years

Other Purposes

Source: CRS.

Securing and Enforcing Patent Protections for

Pharmaceuticals

Pharmaceutical manufacturers often seek to obtain patents on various aspects of their products.

Congress’s power to create the patent system derives from the IP Clause of the U.S. Constitution,

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which grants Congress the power “[t]o promote the Progress of Science and useful Arts, by

securing for limited Times to . . . Inventors the exclusive Right to their . . . Discoveries.”152

Congress has exercised this power since the early days of the Republic to make patent protection

available to inventors.153 The currently operative patent statute is the Patent Act of 1952 (the

Patent Act),154 as amended by laws such as the 2011 Leahy-Smith America Invents Act (AIA).155

This section overviews general patent law principles as they apply to pharmaceutical products,

including common types of pharmaceutical patent claims, the legal rights granted to the holder of

a valid patent, and the authority of the federal government to grant “compulsory licenses” for

patents.

Patent Law Basics

Patents are generally available to anyone who invents a new and useful process, machine, manufacture, or

composition of matter, or any new and useful improvement thereof. To obtain a patent, an inventor must file a

patent application with the U.S. Patent and Trademark Office (PTO). A PTO patent examiner then evaluates the

patent application to determine whether it meets all applicable statutory requirements to merit the grant of a

patent. This process is called patent examination or patent prosecution.

To be patentable, the claimed invention must be (1) directed at patentable subject matter, (2) new, (3)

nonobvious, and (4) useful. Although patentable subject matter is broad, federal courts have held that “products of

nature” may not be patented, which may preclude patenting of unmodified biological material used in

pharmaceuticals. The novelty and nonobviousness requirements preclude patenting inventions that are already

known in the relevant field, or are a trivial variation on what is already known. The usefulness or utility

requirement demands only that the invention have some practice use, and not that the invention be “better” than

the state of existing technology.

Along with these substantive requirements relating to the invention, the Patent Act imposes several requirements

relating to the form of the patent application and the technical information it provides about the claimed invention.

Those provisions ensure that a granted patent adequately discloses the invention to the public so that anyone can

use the invention after the patent term expires.

If granted, the patent’s legal scope is defined by the patent claims. Patent claims must be sufficiently clear and

definite to inform people skilled in the relevant technical field precisely what is covered by the patent, and what is

not,

If granted, patents typically expire 20 years after the date the initial patent application was filed. During this time,

no one else may make, use, sell, or import the invention in the United States without the permission of the patent

holder. A person who practices the invention without the permission of the patent holder is said to infringe the

patent and may be liable in court for monetary damages and other legal remedies.

Sources: 35 U.S.C. §§ 101, 102–103, 111–112, 154, 271; CRS Report R46525, Patent Law: A Handbook for

Congress, coordinated by Kevin J. Hickey (2020).

Types of Pharmaceutical Patent Claims

To be patentable, like any other invention, pharmaceutical-related inventions must be new, useful,

and nonobvious, and they must be sufficiently described in the patent application.156 While

pharmaceutical-related inventions may take a variety of forms, there are several types of claims

often made in connection with pharmaceutical products. For example, if a person is the first to

152 U.S. CONST. art. I, § 8, cl. 8. See generally Cong. Rech. Serv, ArtI.S8.C8.1 Overview of Congress’s Power Over

Intellectual Property, CONSTITUTION Annotated, https://constitution.congress.gov/browse/essay/artI-S8-C8-1/

ALDE_00013060/ (last visited Jan. 29, 2024).

153 See An Act to Promote the Progress of Useful Arts, Pub. L. No. 1-7, 1 Stat. 109 (1790).

154 See Patent Act of 1952, Pub. L. No. 82-593, 66 Stat. 792 (codified as amended at 35 U.S.C. §§ 1–390).

155 Pub. L. No. 112-29, 125 Stat. 284 (2011) (codified in scattered sections of U.S.C. title 35).

156 See 35 U.S.C. §§ 101–103, 112. For more information on the general requirements to obtain a patent, see Hickey,

supra note 28, at 8–17.

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synthesize a particular chemical that she believes to be useful for treating disease, she may obtain

a patent on that chemical itself, generally referred to as the active ingredient.157 Manufacturers

may find patents on a pharmaceutical product’s active ingredient particularly valuable because

these patents may be difficult to “invent around” (i.e., develop a competing product that does not

infringe the patent).158 However, manufacturers of some biological products may not be able to

patent unmodified naturally-occurring active ingredients if they are patent-ineligible subject

matter.159

Manufacturers often obtain many other types of patents relating to a pharmaceutical product

beyond active ingredient patents.160 Pharmaceutical patents may cover many different features of

a drug or biologic beyond a claim on the active ingredient itself.161 Such patents may claim,

among other things,

1. formulations of a pharmaceutical (e.g., an administrable form and dosage, or a

combination of active and other ingredients);

2. methods of using the pharmaceutical (e.g., an indication or use of the drug for

treating a particular disease);

3. technologies and methods used to administer the pharmaceutical (e.g., an inhaler

or injector device);

4. technologies and methods for manufacturing the pharmaceutical (e.g., a

manufacturing process);

5. other chemicals related to the active ingredient, such as crystalline forms,

polymorphs, intermediaries, salts, and metabolites.162

157 See 35 U.S.C. § 101 (allowing patents on “any new and useful . . . composition of matter”).

158 See Margaret K. Kyle, Competition Law, Intellectual Property, and the Pharmaceutical Sector, 81 ANTITRUST L.J.

1, 2 (2016) (“[A]t least one type of pharmaceutical patent, the product patent on the molecule itself, is particularly hard

to invent around.”).

159 See generally Ass’n for Molecular Pathology v. Myriad Genetics, Inc., 569 U.S. 576, 580, 589–96 (2013)

(discussing the “natural phenomena” category of patent-ineligible subject matter and holding that a “naturally occurring

DNA segment is a product of nature and not patent eligible”); Priti Deka Phukan, Patenting Proteins After Myriad, 23

FED. CIR. B.J. 619, 621 (2014) (analyzing “whether synthetically produced biological compounds,” such as therapeutic

proteins and hormones, are patentable “when the synthetic compound is indistinguishable from the naturally occurring

compound”). Biologics that derive from biological organisms, but are genetically modified or otherwise modified by

man into a non-naturally occurring form, are generally patent-eligible. See Diamond v. Chakrabarty, 447 U.S. 303,

309–10 (1980) (upholding patent on genetically engineered bacterium).

160 See Kyle, supra note 158, at 6 (“[T]he primary patent on the molecule is rarely the only one associated with a drug.

Typically, the innovator (or others) files additional patent applications [that] may cover methods of manufacturing the

chemical or biological substance, purified forms, new salts or esters, new uses of the substance, new combinations, new

delivery routes, etc.”).

161 Studies have found that active ingredient patents are a minority of pharmaceutical patents. See Amy Kapczynski et

al., Polymorphs and Prodrugs and Salts (Oh My!): An Empirical Analysis of “Secondary” Pharmaceutical Patents, 7

PLOS ONE 1, 4–6 (2012) (surveying patents listed in FDA’s Orange Book for new chemical entities and finding that

secondary patents, such as formulations and methods of use, were more common than active ingredient patents); Tahir

Amin & Aaron S. Kesselheim, Secondary Patenting of Branded Pharmaceuticals: A Case Study of How Patents on

Two HIV Drugs Could Be Extended for Decades, 31 HEALTH AFFS. 2286, 2289 (2012) (finding that only about 1% of

the 108 patents covering particular HIV drugs claimed the active ingredient, with around 39% claiming formulations

and related chemicals, 32% claiming manufacturing processes, 15% claiming methods of treatment, and 13% claiming

other aspects); see also Robin Feldman, May Your Drug Price Be Evergreen, 5 J.L. & BIOSCI. 590, 637 tbl. 9 (2018)

(finding that most patents added to the Orange Book were associated not with newly approved drugs, but with existing

ones).

162 See JOHN R. THOMAS, PHARMACEUTICAL PATENT LAW 46–64 (3d ed. 2015) (overviewing these and other categories

of pharmaceutical patent claims).

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In addition, if a person invents an improvement on any of these technologies—for example, a new

formulation of the drug, a new use for an existing drug, or a different manufacturing process—

then the inventor can file for a patent on that improvement, which receives its own patent term.163

To be patentable, the improvement must be new and nonobvious, that is, “more than the

predictable use of prior art elements according to their established functions.”164 While it must be

new and nonobvious, the “improvement” need not be actually better than the existing state of the

art to be patentable.165 Any person wishing to practice the improved form of the invention would

need permission from both the patent holder of the original technology and the holder of the

improvement patent (who need not be the same entity), if neither patent has yet expired.166 If the

original patent has expired but the improvement patent has not, permission from the improvement

patentee is needed to practice the improved version, but as a matter of patent law, any person is

free to make and use the original, unimproved version.167

Because many different aspects of pharmaceutical products (and improvements thereto) are

patentable, dozens of different patents may protect some pharmaceutical products. On average,

studies typically find that each drug in the Orange Book is associated with around three listed

patents,168 although recent studies have found that this average has increased over the past

decade.169 This number may understate the size of some pharmaceutical patent portfolios for

several reasons: (1) only some patents relating to a drug may be included in the Orange Book;170

(2) most studies focus on chemical drugs and exclude biologics; and (3) there is evidence that

patent portfolios tend to be larger for particularly lucrative pharmaceutical products.171 Studies

that include biologics, non-Orange Book patents, or focus on top-selling products therefore tend

to find larger average patent portfolios.172

163 35 U.S.C. § 101 (“Whoever invents or discovers any new and useful process, machine, manufacture, or composition

of matter, or any new and useful improvement thereof, may obtain a patent therefor. . . . ” (emphasis added)).

164 KSR Int’l Co. v. Teleflex, Inc., 550 U.S. 398, 417 (2007).

165 See Gene Quinn, The Successful Inventor: Patenting Improvements, IPWATCHDOG (May 3, 2014),

https://ipwatchdog.com/2014/05/03/the-successful-inventor-patenting-improvements/id=49396/ (“[T]here is not a

requirement that an invention actually be an improvement in any real world sense in order for it to be patented . . .

when patent attorneys and patent agents talk about an improvement patent we are typically talking about inventions that

build upon and/or somehow relate to the prior art.”).

166 See Robert Merges, Intellectual Property Rights and Bargaining Breakdown: The Case of Blocking Patents, 62

TENN. L. REV. 75, 80–82 (1994) (analyzing “blocking patents” situation where holder of improvement patent and

holder of the original patent need each other’s permission before either can practice the improved invention).

167 Id. at 91; see also Mark A. Lemley, The Economics of Improvement in Intellectual Property Law, 75 TEX. L. REV.

989, 991, 1010 (1997).

168 See Lisa Larrimore Ouellette, How Many Patents Does It Take to Make a Drug? Follow-On Pharmaceutical Patents

and University Licensing, 17 MICH. TELECOMM. & TECH. L. REV. 299, 314 (2010) (finding, on average, 2.97 patents

listed per drug in FDA’s Orange Book); C. Scott Hemphill & Bhaven N. Sampat, Evergreening, Patent Challenges,

and Effective Market Life in Pharmaceuticals, 31 J. HEALTH ECON. 327, 330 (2012) finding 2.7 patents per drug for

drugs subject to generic entry between 2001 and 2010).

169

See Dr. Omar Robles et al., Economics in Life Sciences: What the Orange Book Reveals About Trends in Patent

Density, Evergreening, and Exclusivity, NAT’L ECON. RSCH. ASSOCS. (June 26, 2020), https://www.nera.com/content/

dam/nera/publications/2020/PUB_LS-Orange-Book_062620.pdf (finding increase in number of over listed patents per

drug over 2011-2018, up to a high of 8 patents per drug in 2018); C. Scott Hemphill & Bhaven N. Sampat, When Do

Generics Challenge Drug Patents, 8 J. EMPIRICAL LEGAL STUD. 613, 620 fig. 1 (2011) (finding increase in number for

Orange Book patents per drug from 2 for drugs approved in 1985 to 4 for drugs approved in 2002).

170 See infra notes 283–284 and accompanying text.

171 See, e.g., Amy Kapczynski et al., Polymorphs and Prodrugs and Salts (Oh My!): An Empirical Analysis of

‘‘Secondary’’ Pharmaceutical Patents, 7 PLoS One 1, 8 tbl. 4 (Dec. 2012).

172 See I-MAK, OVERPATENTED, OVERPRICED (Sept. 2022) (finding 74 patents per product, on average, for the top ten

(continued...)

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To take one well known example, AbbVie obtained over 100 patents related to its biologic,

Humira, covering various formulations, methods of using the biologic, methods of manufacturing

the biologics, and the like.173 As discussed below, there is a significant public policy debate over

such patent portfolios, particularly over the number, timing, and enforcement of nonactive

ingredient patents (sometimes called “secondary” patents).174

Patent Enforcement

Rights of Patent Holders

Once granted, the holder of a valid patent has the exclusive right to make, use, sell, or import the

invention in the United States until the patent expires.175 Any other person who practices the

invention (i.e., makes, uses, sells, offers to sell, or imports it) without permission from the patent

holder infringes the patent and is liable for monetary damages, and possibly injunctive relief, if

sued by the patentee.176 Patents have the attributes of personal property, so the patentee may sell

or assign the patent to another person.177 A patentee may also license other persons to practice the

invention, granting them permission to make, use, sell, or import the invention, usually in

exchange for consideration (such as monetary royalties).178

Patents thus provide a negative right to prevent another person from practicing the claimed

invention. But patents do not grant the patentee any affirmative right to practice the invention.179

In the pharmaceutical context, this means that even if a manufacturer has a patent on a particular

drug (or inventions related to making or using that drug), it still cannot market that drug without

FDA approval.180

Patents are not self-enforcing: to obtain relief from infringement, the patentee must typically sue

in court.181 Patent law is an area of exclusive federal jurisdiction,182 and the traditional forum for

most patent disputes is federal district court.183 Although patent suits may be filed in any district

best-selling drugs and biologics), https://www.i-mak.org/wp-content/uploads/2022/09/Overpatented-Overpriced-2022FINAL.pdf. I-MAK’s methodology, particularly its use of patent applications in determining potential years of

exclusivity, has been criticized by some scholars and Members of Congress. See Adam Mossoff, Unreliable Data Have

Infected the Policy Debates over Drug Patents, HUDSON INST. (Jan. 19, 2022), https://www.hudson.org/technology/

unreliable-data-have-infected-the-policy-debates-over-drug-patents; Letter from Sen. Thom Tillis to Tahir Amin, CoExecutive Director, I-MAK (Jan 31. 2022), https://ipwatchdog.com/wp-content/uploads/2022/02/1.31.2022-LTR-fromSenator-Tillis-to-IMAK-re-Patent-Data-Sources.pdf.

173 Mayor and City Council of Baltimore v. AbbVie Inc., 42 F.4 th 709, 710 (7th Cir. 2022).

174 See infra “Pharmaceutical Patenting Practices.”

175 35 U.S.C. § 271(a).

176 Id. §§ 271, 281, 283–85.

177 Id. § 261.

178 License, BLACK’S LAW DICTIONARY (10th ed. 2014); 35 U.S.C. § 271(a).

179 Leatherman Tool Grp. v. Cooper Indus., Inc., 131 F.3d 1011, 1015 (Fed. Cir. 1997) (“[T]he federal patent laws do

not create any affirmative right to make, use, or sell anything.”).

180 See supra “New and Generic Drug Approval” and “Biological Product and Biosimilar Licensure.”

181 35 U.S.C. § 281.

182 28 U.S.C. § 1338.

183 Along with district court and the Patent Trial and Appeal Board (PTAB), see infra “The Patent Trial and Appeal

Board,” the third main forum for patent disputes is the International Trade Commission (ITC), which has authority to

conduct administrative trials (called “section 337 investigations”) into whether imported goods violate patent and other

IP rights. See 19 U.S.C. § 1337. The ITC may issue exclusion orders to stop such goods from entering the United

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court across the country with jurisdiction over the defendant and proper venue,184 all appeals in

patent cases are heard by a single specialized court, the U.S. Court of Appeals for the Federal

Circuit.185

Patent Term and Effective Exclusivity Periods

With some exceptions, a patent is granted “for a term beginning on the date on which the patent

issues and ending 20 years from the date on which the application for the patent was filed.”186 The

Patent Act includes provisions that may modify the 20-year term, including to account for

excessive delays in patent examination at the PTO,187 or delays associated with obtaining

marketing approval from other federal agencies (including FDA).188 In the pharmaceutical

context, the PTO may extend the term of patents claiming a drug product or medical device (or a

method of using or manufacturing the same) for up to five years to account for delays in

obtaining regulatory approval, if certain statutory conditions are met.189

Precisely when generic or biosimilar competition occurs for any given product depends on a

complex interplay of market incentives, patents, regulatory exclusivities, FDA processes, and—

not infrequently—litigation.190 New drugs and biologics are commonly protected by both patents

and FDA regulatory exclusivities. Although patents can last up to 20 years, some of the patent

term is taken up by the patent application process itself or occurs prior to market approval for a

drug or biologic, particularly for patents granted early in a product’s life cycle.191 In addition,

although patents carry a presumption of validity,192 they may be challenged by generic and

biosimilar manufacturers, as discussed in detail below.193

States. See About Section 337, U.S. INT’L TRADE COMM., https://www.usitc.gov/intellectual_property/

about_section_337.htm (last visited Jan. 26, 2024); see generally Sapna Kumar, The Other Patent Agency:

Congressional Regulation of the ITC, 61 FLA. L. REV. 529, 534–40 (2009) (overviewing ITC procedures). In contrast to

the thousands of cases heard by the PTAB and district courts, the ITC typically initiates several dozen section 337

investigations per year. See Section 337 Statistics: Number of New, Completed, and Active Investigations by Fiscal

Year, U.S. INT’L TRADE COMM. (Oct. 15. 2020), https://www.usitc.gov/intellectual_property/

337_statistics_number_new_completed_and_active.htm (reporting 58 new complaints in Fiscal Year 2019).

184 Patent cases must be brought in a judicial district where the defendant resides (i.e., its state of incorporation), or has

a regular and established place of business. See 28 U.S.C. § 1400(b); TC Heartland v. Kraft Foods Grp. Brands, 581

U.S. 258, 262 (2017); In re Cray, 871 F.3d 1355, 1362–64 (Fed. Cir. 2017).

185 28 U.S.C. § 1295(a)(1).

186 35 U.S.C. § 154(a)(2).

187 Id. § 154(b)(1).

188 Id. § 156.

189 See Eli Lilly & Co. v. Medtronic, Inc., 496 U.S. 661, 670–71 (1990); Merck & Co. v. Hi-Tech Pharmacal Co., 482

F.3d 1317, 1320–21 (Fed. Cir. 2007); see generally Stephanie Plamondon Bair, Adjustments, Extensions, Disclaimers,

and Continuations: When Do Patent Term Adjustments Make Sense?, 41 CAP. U. L. REV. 445 (2013).

190 See CRS In Focus IF11214, Drug Pricing and the Law: Pharmaceutical Patent Disputes, by Kevin J. Hickey

(2019).

191 See generally Aaron S. Kesselheim et al., Determinants of Market Exclusivity for Prescription Drugs in the United

States, 177 JAMA INTERNAL MED. 1658, 1658–59 (2017), https://jamanetwork.com/journals/jamainternalmedicine/

fullarticle/2653014. Patent term extensions may compensate for lost effective exclusivity period consumed by

regulatory review. See 35 U.S.C. § 156.

192 See Microsoft Corp. v. i4i Ltd., 564 U.S. 91, 95 (2011).

193 See infra “Patent Dispute Procedures for Generic Drugs and Biosimilars.”

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In practice, empirical studies usually find that the average effective market exclusivity period for

new drugs (i.e., the average time before actual generic entry) is between 12 and 15 years.194

Although data is limited, some studies show that average effective exclusivity periods are longer

for biologics.195 This may be due to market and patenting factors, or the longer general regulatory

exclusivity period (12 years) for new biologics.196

Defenses to Claims of Patent Infringement

Parties accused of patent infringement may defend on several grounds. First, although patents are

subject to a presumption of validity, the accused infringer may assert that the patent is invalid.197

To prove invalidity, the accused infringer must show, by clear and convincing evidence, that the

PTO should not have granted the patent because it failed to meet the requirements for

patentability.198 Thus, for example, the accused infringer may argue that the invention lacks

novelty, is obvious, or claims nonpatentable subject matter; that the patent fails to sufficiently

describe or enable the invention; or that the patent claims are indefinite.199 Second, the accused

infringer may argue that it is not liable based on noninfringement.200 In other words, even

presuming the patent is valid, the patentee may fail to prove that the actions of the accused

infringer fall within the scope of the patent claims.201 Finally, the accused infringer may argue the

patent is unenforceable based on the patent holder’s inequitable or illegal activities, such as

obtaining the patent through fraud on the PTO.202

194 See Henry Grabowski et al., Continuing Trends in U.S. Brand-name and Generic Drug Competition, 24 J. MED.

ECON. 908, 908 (2021) (finding average market exclusivity period of 14.1 years for all drugs with generic entry between

2017 and 2019, and an average of 13 years for drugs with sales over $250 million); Benjamin N. Rome et al., Market

Exclusivity Length for Drugs with New Generic or Biosimilar Competition, 2012–2018, 109 CLINICAL PHARM &

THERAPEUTICS 367 (2020) (finding average market exclusivity of 14.4 years); Erika Lietzan & Kristina M.L. Acri née

Lybecker, Distorted Drug Patents, 95 WASH. L. REV. 1317, 1363 (2020) (finding an average effective market

exclusivity period of 12.6 years for drugs with restored patent terms under the Hatch-Waxman Act); Henry Grabowski

et al., Updated Trends in U.S. Brand-Name and Generic Drug Competition, 19 J. MED. ECON. 836, 836 (2016) (finding

average effective exclusivity period of 13.6 years for all drugs with generic entry between 1995 and 2014, and an

average of 12.5 years for drugs with sales over $250 million); Bo Wang et al., Variations in Time of Market Exclusivity

Among Top-Selling Prescription Drugs in the United States, 175 JAMA INTERNAL MED. 635, 636 (2015) (finding an

average effective market exclusivity of 12.5 years for top-selling drugs between 2000 and 2012); Hemphill & Sampat,

supra note 168, at 336 (finding an average market exclusivity of 12.2 years that was “stable” over the decade studied).

195 See Rome et al., supra note 194, at 368 (finding average effective market exclusivity of 21.56 years for the four

biologics in the study).

196 42 U.S.C. § 262(k)(7).

197 35 U.S.C. § 282(a)–(b).

198 Id. § 282(b)(2)–(3); Microsoft Corp. v. i4i Ltd. P’ship, 564 U.S. 91, 95–96 (2011).

199 See 35 U.S.C. §§ 101, 102–03, 112, 282(b)(2)–(3).

200 Id. § 282(b)(1).

201 To prove direct infringement, the plaintiff must show that each element contained in a patent claim is practiced by

the alleged infringer, either literally or by an equivalent. Warner-Jenkinson Co. v. Hilton Davis Chem. Co., 520 U.S.

17, 29–30 (1997). Often, whether or not the accused infringer’s activities fall within the patent claims depends upon

claim construction, that is, how the words used in the patent claims are interpreted. See generally Markman v.

Westview Instruments, Inc., 517 U.S. 370, 372–74 (1996); Phillips v. AWH Corp., 415 F.3d 1303, 1312–19 (Fed. Cir.

2005) (en banc).

202 See Therasense, Inc. v. Becton, Dickinson & Co., 649 F.3d 1276, 1285, 1290–91 (Fed. Cir. 2011) (en banc).

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Remedies for Patent Infringement

If the patentee succeeds in proving infringement, the patent holder may obtain two major forms of

judicial relief: monetary damages and injunctive relief.203 Damages must be “adequate to

compensate for the infringement.”204 Typically, courts will award either (1) lost profits (the net

revenue “lost to the patentee because of the infringement”),205 or (2) a reasonable royalty (the

amount the patentee would have received in a “hypothetical negotiation” if the patentee and the

infringer had negotiated a good-faith license).206 Courts may increase these damages “up to three

times the amount found or assessed,”207 but such enhanced damages are “generally reserved for

egregious cases of culpable behavior” by the infringer.208 Finally, courts may award attorneys’

fees in “exceptional cases”209 that “stand[] out from others with respect to the substantive strength

of a party’s litigating position” or “the unreasonable manner in which the case was litigated.”210

A patent holder may also ask a court to order various forms of injunctive relief.211 At the outset of

a patent litigation, a patent holder may seek a preliminary injunction, a court order that prevents

the defendant from committing the allegedly infringing acts while the litigation proceeds.212 If a

patentee prevails in an infringement lawsuit, the patent holder may seek a permanent injunction, a

final order prohibiting the defendant from infringing the patent in the future.213

The Patent Trial and Appeal Board

Following its creation through the AIA in 2011, the PTO’s Patent Trial and Appeal Board (PTAB)

has become an increasingly important forum for patent disputes.214 The AIA created several new

administrative procedures for challenging patent validity,215 including (1) post-grant review

(PGR), which allows petitioners to challenge patent validity based on any of the requirements of

203 35 U.S.C. §§ 283–284. A judicial declaration of the parties’ rights—known as a declaratory judgment—is another

important form of relief in patent suits that is sometimes available to patentees or accused infringers. 28 U.S.C. § 2201;

see also infra note 263.

204 35 U.S.C. § 284.

205 Rite-Hite Corp. v. Kelley Co., 56 F.3d 1538, 1545 (Fed. Cir. 1995) (en banc).

206 Lucent Techs., Inc. v. Gateway, Inc., 580 F. 3d 1301, 1324 (Fed. Cir. 2009).

207 35 U.S.C. § 284.

208 Halo Elecs., Inc. v. Pulse Elecs., Inc., 579 U.S. 93, 104 (2016).

209 35 U.S.C. § 285.

210 Octane Fitness, LLC v. ICON Health & Fitness, Inc., 572 U.S. 545, 554 (2014).

211 35 U.S.C. § 283.

212 In deciding whether to exercise their discretion to grant a motion for a preliminary injunction, courts weigh four

factors: (1) the likelihood that the plaintiff will succeed on the merits of the lawsuit; (2) whether the plaintiff is likely to

suffer irreparable harm in the absence of a preliminary injunction; (3) the balance of equities; and (4) whether an

injunction is in the public interest. See Titan Tire Corp. v. Case New Holland, Inc., 566 F.3d 1372, 1375–76 (Fed. Cir.

2009) (citing Winter v. Natural Res. Def. Council, Inc., 555 U.S. 7, 20 (2008)).

213 35 U.S.C. § 283. Courts may grant permanent injunctions to remedy patent infringement as justified by traditional

equitable principles, but injunctions are not issued solely because the patent holder succeeds in proving infringement.

See eBay, Inc. v. MercExchange LLC, 547 U.S. 388, 394 (2006).

214 See generally Rochelle Cooper Dreyfuss, Giving the Federal Circuit a Run for Its Money: Challenging Patents in

the PTAB, 91 NOTRE DAME L. REV. 235, 249 (2015); Hickey, supra note 28, at 24–28 (reviewing PTAB proceedings).

215 Prior to the AIA, the PTO administered two earlier administrative mechanisms to challenge patents. The first, inter

partes reexamination, was generally considered to be “underutilized” and has been replaced by IPR. See Dreyfuss,

supra note 214, at 235 n.2; Brian J. Love & Shawn Ambwani, Inter Partes Review: An Early Look at the Numbers, 81

U. CHI. L. REV. DIALOGUE 93, 95–96 (2014). The second, ex parte reexamination, which was left unchanged by the

AIA, permits the PTO to reopen patent prosecution if a “substantial question of patentability” is presented based on

certain prior art cited by the patentee or a third party to the PTO. 35 U.S.C. §§ 301–307.

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patentability if the PGR petition is filed within nine months of the patent’s issuance;216 and (2)

inter partes review (IPR), which allows any person other than the patentee to challenge patent

validity on limited grounds (novelty or obviousness based on prior patents or printed

publications) at any time after nine months following the patent’s issuance.217 PTAB may institute

a PGR or IPR when a petition filed with PTAB establishes a reasonable likelihood that the

petitioner would prevail with respect to at least one of the claims challenged (although the PTAB

retains discretion to deny a petition).218 Of these two procedures, IPR is by far the most widely

used.219

According to a PTO analysis, the majority of IPR petitions concern patents on computer and

electronical technologies.220 About 4% of IPR petitions filed between 2012 and 2023 concern

patents listed in the Orange Book, with an additional 2% concerning biologic patents.221 These

averages are down in recent years from a FY2016 peak of 7.5% IPR petitions challenging Orange

Book patents, and a peak of 3.9% of IPRs challenging biologic patents in FY2017.222 IPR

petitions challenging drug and biologic patents are instituted at lower rates than the overall

average.223

Compulsory Licensing

As explained above, a patent holder generally has the exclusive right to practice an invention.

Any other person who wishes to make, use, sell, or import the invention would ordinarily need a

license (i.e., permission) from the patent holder, or else be exposed to legal liability.224 In certain

cases, however, patents may be subject to a “compulsory license,” which allows another person to

use the invention without the patent holder’s prior consent.225

Compulsory licenses are typically authorized by statute and usually require the sanction of a

governmental entity and payment of compensation to the patent holder.226 Compulsory licenses

differ from ordinary patent licenses in two important respects: (1) the person seeking to use the

invention need not seek advance permission from the patent holder; and (2) the compensation

paid to the patentee is generally determined by operation of law, not by private contractual

negotiations between the licensee and the patent holder.

Current federal law contains several provisions that may be characterized as compulsory licenses

for patents.227 One, 28 U.S.C. § 1498, is sometimes described as an “eminent domain” provision

216 35 U.S.C. §§ 321–329.

217 Id. §§ 311–319.

218 Id. §§ 314, 324.

219 See PTO, PTAB TRIAL STATISTICS: JANUARY 2023 IPR, PGR 3 (2023), https://www.uspto.gov/sites/default/files/

documents/ptab_aia_20230131_.pdf (98% of recently filed PTAB petitions are IPRs).

220 See PTO, PTAB ORANGE BOOK PATENT/BIOLOGIC PATENT STUDY 4 (updated March 31, 2023),

https://www.uspto.gov/sites/default/files/documents/orange_book_biologics_study_update_thru_march__2023_.pdf.

221 Id.

222 Id. at 5–6.

223 Id. at 10.

224 Id. § 271.

225 Compulsory License, BLACK’S LAW DICTIONARY (10th ed. 2014) (“A statutorily created license that allows certain

people to pay a royalty and use an invention without the patentee’s permission.”).

226 See generally Subhasis Saha, Patent Law and TRIPS: Compulsory Licensing of Patents and Pharmaceuticals, 91 J.

PAT. & TRADEMARK OFF. SOC’Y 364, 366–67 (2009).

227 See generally Jesse S. Chui, To What Extent Can Congress Change the Patent Right Without Effecting a Taking?,

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for patents.228 Section 1498 allows the U.S. government to use any patented invention “without

license.”229 The patentee, however, has the right to sue in the U.S. Court of Federal Claims for

“reasonable and entire compensation” for the government’s use of the patented invention.230 A

court, though, would not issue an injunction against the United States to prevent its use of the

invention.231 In effect, then, section 1498 allows the United States to issue itself a compulsory

license to use any patented invention without obtaining the patentee’s permission in exchange for

the payment of reasonable compensation.232 This compulsory license may extend to federal

contractors, subcontractors, and any person acting “with the authorization or consent of the [U.S.]

Government.”233 The federal government relies on section 1498 authority with some frequency,234

particularly in the defense context.235 In the pharmaceutical context, however, the United States

has not used section 1498 in recent decades.236

Compulsory licensing is also available for inventions made with federal funding under the BayhDole Act.237 In general, Bayh-Dole permits certain government contractors to obtain patents on

inventions produced with federal funding.238 However, the federal government retains the

authority to “march in” and grant compulsory licenses to third parties for federally funded

inventions under certain specified circumstances, such as the patent holder’s failure to practice

the patented invention or health or safety needs.239 A license granted under Bayh-Dole’s march-in

34 HASTINGS CONST. L.Q. 447, 462–66 (2007) (reviewing examples of compulsory licensing provisions in existing law,

including 28 U.S.C. § 1498, and provisions of the Clean Air Act, Atomic Energy Act, Invention Secrecy Act, and Plant

Variety Protection Act).

228 See Motorola, Inc. v. United States, 729 F.2d 765, 768 (Fed. Cir. 1984); Leesona Corp. v. United States, 599 F.2d

958, 964 (Ct. Cl. 1979).

229 28 U.S.C. § 1498(a).

230 Id.

231 Advanced Software Design Corp. v. Fed. Reserve Bank of St. Louis, 583 F.3d 1371, 1375 (Fed. Cir. 2009)

(“[Section 1498] has the effect of removing the threat of injunction. . . . ”); Motorola, 729 F.2d at 768 n.3.

232 Amanda Mitchell, Tamiflu, the Takings Clause, and Compulsory Licenses: An Exploration of the Government’s

Options for Accessing Medical Patents, 95 CAL. L. REV. 535, 541–42 (2007) (analogizing section 1498 to a compulsory

license).

233 28 U.S.C. § 1498(a).

234 Hannah Brennan et al., A Prescription for Excessive Drug Pricing: Leveraging Government Patent Use for Health,

18 YALE J.L. & TECH. 275, 302 (2016) (characterizing the government’s use of section 1498 as “routine” and citing a

number of examples); but see Adam Mossoff, The False Promise of Breaking Patents to Lower Drug Prices ST. JOHN’S

L. REV. (forthcoming 2024), https://papers.ssrn.com/sol3/papers.cfm?abstract_id=4348499 (manuscript at 7–12)

(arguing that section 1498 cannot be used to lower drug prices because it does not apply to goods sold to private

parties).

235 See, e.g., FastShip, LLC v. United States, 892 F.3d 1298 (Fed. Cir. 2018); Beacon Adhesives, Inc. v. United States,

134 Fed. Cl. 26 (2017); Ensign-Bickford Aerospace & Def. Co. v. United States, 118 Fed. Cl. 363 (2014).

236 Brennan et al., supra note 234, at 303–07 (describing various uses of section 1498 by the federal government to

purchase pharmaceutical drugs in the 1960s, but observing this practice “tailed off in the 1970s”). The only recent

invocation of section 1498 in the health context occurred in 2001, when Tommy Thompson, then-Secretary of HHS,

threatened to (but ultimately did not) rely on this authority to purchase generic versions of Cipro during the anthrax

scare. Id. at 303.

237 See Pub. L. No. 96-517, § 6, 94 Stat. 3015, 3019–27 (1980).

238 35 U.S.C. § 202(a).

239 35 U.S.C. § 203(a)(1)–(4). See generally Jennifer Penman & Fran Quigley, Better Late than Never: How the U.S.

Government Can and Should Use Bayh-Dole March-in Rights to Respond to the Medicines Access Crisis, 54

WILLAMETTE L. REV. 171, 177–78 (2017). There is a longstanding debate over whether high drug prices could support

the exercise of march-in rights. Compare, e.g., Mossoff, supra note 234, at 23–30 (arguing that the statute does not

authorize march-in based on high prices) with Peter S. Arno & Michael H. Davis, Why Don’t We Enforce Existing

Drug Price Controls? The Unrecognized and Unenforced Reasonable Pricing Requirements Imposed upon Patents

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provisions must be “upon terms that are reasonable under the circumstances,” which may require

the licensee to pay some compensation to the patentee.240 The federal government has never

exercised its march-in rights under Bayh-Dole.241

Some stakeholders and Members of Congress have urged the federal government to make greater

use of these compulsory licensing authorities as a means to authorize generic competition and

potentially lower prices for certain drugs.242 Others argue that these statutory authorities do not

support compulsory licensing as a means to control drug prices, or that using them in this way

would undermine incentives for innovation in drug development.243 In December 2023, the

National Institute of Standards and Technology (which has relevant regulatory authority to

implement the Bayh-Dole Act) published draft guidance suggesting that agencies may consider

the patented product’s price, among other factors, when deciding whether to exercise march-in

rights.244 The Biden Administration touted the draft guidance as a way to promote competition

and lower prescription drug costs.245 Critics contended that Bayh-Dole does not permit agencies

to consider pricing and that the potential use of march-in rights would undermine pharmaceutical

innovation and investment in R&D.246

Deriving in Whole or in Part from Federally Funded Research, 75 TULANE L. REV. 631, 649–53 (arguing that high

prices can be used as the basis to invoke march-in rights). See generally Glenn Kessler, The Claim That the U.S.

Government Already Has the Power to Lower Drug Prices, WASH. POST (Sept. 8, 2021),

https://www.washingtonpost.com/politics/2021/09/08/claim-that-us-government-already-has-power-lower-drug-prices/

(overviewing this legal debate).

240 35 U.S.C. § 203(a); Penman & Quigley, supra note 239, at 178.

241 Penman & Quigley, supra note 239, at 199.

242 See, e.g., Brennan et al., supra note 234, at 353–54 (arguing that section 1498 should be used to lower prices and

increase access to life-saving medicines); Letter from Sen. Elizabeth Warren, Sen, Angus S. King, and Rep. Lloyd

Doggett to Xavier Becerra, Secretary of the Department of Health and Human Services (Feb. 17, 2022),

https://www.warren.senate.gov/imo/media/doc/

2022.02.17%20Letter%20to%20Sec.%20Becerra%20on%20Xtandi%20March-in%20Petition%20(2).pdf (urging the

government to exercise march-in rights in order to lower prices for the prostate cancer drug enzalutamide).

243 See, e.g., Mossoff, supra note 234, at 4-5 (arguing that neither section 1498 nor the Bayh-Dole Act authorizes the

use of compulsory licensing to impose price controls); BAYH-DOLE COALITION, ISSUE BRIEF: MARCH-IN RIGHTS UNDER

THE BAYH-DOLE ACT (2023), https://bayhdolecoalition.org/wp-content/uploads/2023/02/BDC-Issue-Brief-March-inRights.pdf (arguing that invoking march-in rights to control prices would be highly detrimental to innovation).

244 See NIST, Request for Information Regarding the Draft Interagency Guidance Framework for Considering the

Exercise of March-In Rights, 88 Fed. Reg. 85593 (Dec. 8, 2023).

245 Press Release, FACT SHEET: Biden-⁠Harris Administration Announces New Actions to Lower Health Care and

Prescription Drug Costs by Promoting Competition (Dec. 7, 2023), https://www.whitehouse.gov/briefing-room/

statements-releases/2023/12/07/fact-sheet-biden-harris-administration-announces-new-actions-to-lower-health-careand-prescription-drug-costs-by-promoting-competition/.

246 See, e.g., Joel Zinberg, Biden Decides to “March In” on Drug Prices, WALL ST. J. (Dec. 12, 2023),

https://www.wsj.com/articles/biden-decides-to-march-in-on-drug-patents-price-control-biotech-research-3e327f6b

(arguing that the guidance “will stifle pharmaceutical innovation and harm Americans’ health”); Joseph Allen, New

March-in Guidelines Threaten U.S. Innovation, IPWATCHDOG (Dec. 10, 2023), https://ipwatchdog.com/2023/12/10/

new-march-guidelines-threaten-u-s-innovation/id=170491/.

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Patent Dispute Procedures for Generic Drugs and

Biosimilars

As Table 2 summarizes, patent rights granted by the PTO and regulatory exclusivities granted by

FDA are legally distinct.247 They are motivated by similar purposes. Patents seek to encourage

innovation by providing an economic incentive for inventors to invest their time and resources in

developing novel inventions.248 Analogously, regulatory exclusivities granted by FDA249 provide

an incentive for pharmaceutical manufacturers to undertake the investments necessary to

complete the FDA approval process and bring new drugs and biologics to market.250

In some circumstances, patent rights can affect when a manufacturer can market a generic drug or

biosimilar. For example, if a court hearing a patent dispute grants an injunction that prohibits a

manufacturer from infringing by making a generic drug, the manufacturer cannot bring that

product to market until after the patent expires and the injunction terminates.251 In addition, as

discussed below, the Hatch-Waxman Act’s specialized patent dispute procedures can affect FDA’s

ability to approve an ANDA, even prior to a judicial decision.252 Patent rights may also affect

follow-on market entry indirectly, if a generic or biosimilar manufacturer declines to seek FDA

approval because of the number of existing patents relating to a product or the anticipated costs of

challenging them.253

247 See generally Rebecca S. Eisenberg, Patents and Regulatory Exclusivity, in THE OXFORD HANDBOOK OF THE

ECONOMICS OF THE BIOPHARMACEUTICAL INDUSTRY 167–200 (Patricia M. Danzon & Sean Nicholson eds., 2012).

248 See Kewanee Oil Co. v. Bicron Corp., 416 U.S. 470, 480 (1974) (“The patent laws promote [the progress of the

useful arts] by offering a right of exclusion for a limited period as an incentive to inventors to risk the often enormous

costs in terms of time, research, and development.”).

249 See supra “Regulatory Exclusivities.”

250 See Ward, supra note 31, at 1; Morgan, supra note 26, at 98.

251 See supra “Rights of Patent Holders.”

252 See infra “The Hatch-Waxman Act: Patents and Generic Drug Approval.”

253 If these existing patents are valid, such deterrence is the object of a functioning patent system. In some cases,

patents may deter competition even if a court was likely to hold the patents invalid or not infringed. See generally

Christopher R. Leslie, The Anticompetitive Effects of Unenforced Invalid Patents, 91 MINN. L. REV. 101, 113–39

(2006) (arguing that even invalid patents can deter market entry of competitors based on fear of litigation and high

litigation costs); Rebecca S. Eisenberg & Daniel A. Crane, Patent Punting: How FDA and Antitrust Courts Undermine

the Hatch-Waxman Act to Avoid Dealing with Patents, 21 MICH. TELECOMM. & TECH. L. REV. 197, 260–62 (2015)

(arguing that pharmaceutical companies may deter or delay competition through assertion of “irrelevant” patents).

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Table 2. Summary Comparison of Patents Versus Regulatory Exclusivities

Patents

Regulatory Exclusivities

Purpose

Provide incentives to encourage creation

of new technologies

Balance pharmaceutical innovation and generic

competition

Specific to

Pharmaceuticals?

No; available to any “process, machine,

manufacture, or composition of matter”

Yes

Relevant Agency

Patent & Trademark Office (PTO)

Food & Drug Administration (FDA)

Requirements

New, useful, nonobvious, and sufficiently

disclosed invention

Completion of FDA regulatory process for a

particular drug or biological product

Term

Generally 20 years from the date the

relevant patent application was filed

Variable (six months to 12 years) based on

drug type, prior approvals, and other factors

Effect

Third parties cannot make, use, sell, or

import the invention without the

patentee’s permission

Third parties cannot seek, obtain, and/or use

data for FDA approval with respect to

particular product

Enforcement

By the patentee, usually through a patent

infringement lawsuit

By FDA

Source: CRS.

Rationale for Specialized Pharmaceutical Patent Procedures

One of the core aims of the Hatch-Waxman Act was to correct “two unintended distortions” in the

patent term resulting from the patent law’s interaction with FDA premarketing requirements for

drugs and biologics.254 The first distortion affected new drug manufacturers: because obtaining

FDA marketing approval may take years, regulatory requirements shorten the effective patent

term (i.e., the period during which the patentee can derive profit from the invention).255 In

response, the Hatch-Waxman Act granted a patent term extension for certain inventions relating

to drug products or medical devices based on delays in obtaining regulatory marketing

approval.256

The other distortion concerned the end of the patent term and affected generic-drug

manufacturers. In general, once a patent expires, the patented invention should be available for

anyone to use.257 In the pharmaceutical context, generic manufacturers should, in theory, be able

to enter the market shortly after the applicable patents and regulatory exclusivities have expired.

Prior to the Hatch-Waxman Act, however, some judicial decisions held that uses of a patented

drug necessary to obtain FDA approval, such as conducting tests on a patented drug, constituted

patent infringement.258 Thus, as a practical matter, generic manufacturers could often not even

begin seeking FDA approval until the applicable patents expired.259 The result was an “effective

extension of the patent term” based on the “combined effect of the patent law and the premarket

254 Eli Lilly & Co. v. Medtronic, Inc., 496 U.S. 661, 669 (1990).

255 Id. at 669–70.

256 Id. at 670; 35 U.S.C. § 156. The patent term extension applies, among other things, to patents that claim a drug or

medical device, a method of using a drug or medical device, or a method of manufacturing a drug or medical device.

See id. § 156(a), (f)(1).

257 Sears, Roebuck & Co. v. Stiffel Co., 376 U.S. 225, 230 (1964) (“[W]hen the patent expires the monopoly created by

it expires, too, and the right to make the article . . . passes to the public.”).

258 See, e.g., Roche Prods. v. Bolar Pharm. Co., 733 F.2d 858, 863 (Fed. Cir. 1984).

259 Eli Lilly, 496 U.S. at 670.

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regulatory approval requirement.”260 In response, the Hatch-Waxman Act created a “safe harbor,”

providing that making, using, or selling an invention “solely for uses reasonably related to the

development and submission of information under a federal law which regulates the manufacture,

use, or sale of drugs” is not patent infringement.261

A potential side effect of this safe harbor was to limit the ability of a pharmaceutical patent holder

to file a lawsuit for patent infringement prior to the generic manufacturer’s marketing of the

follow-on product.262 If actions relating to the FDA approval process are no longer infringing,

patent litigation against an ANDA filer might not occur until the generic or biosimilar is

marketed, after the completion of the FDA approval process.263 Earlier resolution of patent

disputes is usually regarded as beneficial, as it provides greater legal certainty to both the brandname and generic-drug manufacturers.264 In particular, generic manufacturers can obtain clarity

on patent issues before they market a drug and expose themselves to monetary damages.265

To facilitate early patent dispute resolution, the Hatch-Waxman Act made the filing of an ANDA

or paper NDA an “artificial” act of patent infringement.266 The BPCIA contains an analogous

provision making the filing of a biosimilar or interchangeable BLA an artificial act of patent

infringement.267 Functionally, these artificial acts of infringement enable the brand-name

manufacturer to sue for patent infringement at the time of the follow-on application, allowing

litigation of patent disputes before the generic drug or biosimilar is marketed.268

For all these reasons, both the Hatch-Waxman Act and the BPCIA enacted specialized patent

dispute resolution procedures that complement the abbreviated pathways for the regulatory

approval for follow-on products. This section reviews these procedures.

260 Id.

261 35 U.S.C. § 271(e)(1); Merck KGaA v. Integra Lifescis. I, Ltd., 545 U.S. 193, 200 (2005) (describing this provision

as a “safe harbor”).

262 Eli Lilly, 496 U.S. at 678.

263 Even in the absence of an actual act of infringement, either party could generally file a lawsuit seeking a declaratory

judgment, asking a court to “declare the rights and other legal relations” between the parties, such as whether a patent is

invalid or noninfringed. 28 U.S.C. § 2201(a). For a court to have jurisdiction, there must be an actual and “substantial

controversy, between parties having adverse legal interests, of sufficient immediacy and reality to warrant the issuance

of a declaratory judgment.” MedImmune, Inc. v. Genentech, Inc., 549 U.S. 118, 127 (2007) (quoting Md. Cas. Co. v.

Pac. Coal & Oil Co., 312 U.S. 270, 273 (1941)); see also Teva Pharm. USA, Inc. v. Novartis Pharm. Corp., 482 F.3d

1330, 1336–39 (Fed. Cir. 2007). In addition, both the Hatch-Waxman Act and the BPCIA limit declaratory judgement

jurisdiction for pharmaceutical patents in some circumstances. 28 U.S.C. § 2201(b).

264 See Natalie M. Derzko, The Impact of Recent Reforms of the Hatch-Waxman Scheme on Orange Book Strategic

Behavior and Pharmaceutical Innovation, 45 IDEA: INTELL. PROP. L. REV. 165, 239 (2005) (“From society’s

perspective, early resolution of such patent disputes is generally considered beneficial since it helps clear the way for

generic drug entry if a patent is in fact invalid. . . . Such resolution provides an early signal to the generic company of

this fact before substantial resources are expended in launching, marketing and selling its generic copy of the brandname drug.”).

265 See id. at 239–40; Laura J. Robinson, Analysis of Recent Proposals to Reconfigure Hatch-Waxman, 11 J. INTELL.

PROP. L. 47, 78 (2003) (“[If patent issues are not resolved,] the generic [company] cannot go to market without risking

a later infringement suit with substantial damages.”).

266 Eli Lilly, 496 U.S. at 678; see 35 U.S.C. § 271(e)(2)(A).

267 35 U.S.C. § 271(e)(2)(C).

268 Eli Lilly, 496 U.S. at 678; see generally Elizabeth Stotland Weiswasser & Scott D. Danzis, The Hatch-Waxman Act:

History, Structure, and Legacy, 71 ANTITRUST L.J. 585, 595 (2003) (“The Hatch-Waxman Act created a system that

enabled the resolution of patent infringement disputes prior to the entry of generic competition.”).

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The Hatch-Waxman Act: Patents and Generic Drug Approval

Paragraph I-IV Certifications and Interaction with FDA Approval

Under the Hatch-Waxman Act, a drug manufacturer must list, as part of its NDA, any patent that

claims the drug that is the subject of the application, or a method of using that drug.269 FDA

includes information on listed patents in the Orange Book.270 When a generic drug manufacturer

files an ANDA, it must provide a certification for each patent listed in the Orange Book for the

RLD.271 Figure 1 diagrams the patent dispute process under the Hatch-Waxman Act.

In particular, with some exceptions,272 the generic applicant must make one of four certifications

for each listed patent:

(I) there is no patent information listed;

(II) the patent has expired;

(III) the date the patent will expire; or

(IV) the patent is invalid or not infringed by the generic applicant’s product.273

Paragraph I and II certifications do not affect FDA’s ability to approve the ANDA.274 If the

generic applicant makes a paragraph III certification, FDA may not approve the ANDA until the

patent at issue has expired.275

A paragraph IV certification triggers Hatch-Waxman’s specialized patent dispute procedures,

often leading to litigation.276 First, the generic applicant must give notice of the ANDA and the

paragraph IV certification to the patentee and the NDA holder, including “a detailed statement of

the factual and legal basis” for patent invalidity or noninfringement.277 The NDA or patent holder

then has 45 days to sue the generic applicant for patent infringement.278 If the NDA or patent

holder declines to sue by the deadline, the generic applicant may file a “civil action to obtain

patent certainty” to obtain a declaratory judgment that the Orange Book-listed patents are invalid

or not infringed.279

If the patent holder timely files suit after being notified of the paragraph IV certification, this

lawsuit triggers the “30-month stay”: FDA generally cannot approve the ANDA for 30 months

269 21 U.S.C. § 355(b)(1); see also 21 C.F.R. § 314.53(b).

270 See Orange Book, supra note 118.

271 21 U.S.C. § 355(j)(2)(A)(vii). While this summary discusses the patent dispute procedures with respect to an

ANDA, NDAs that rely on reports and data to which they have no right of reference (e.g., published studies) are subject

to a parallel certification and notification process. See id. § 355(b)(2)–(3), (c)(3).

272 With respect to patents that claim a method of using a drug, the generic applicant may file a “section viii” statement

when the applicant is seeking approval only for a use that is not claimed in a listed patent. Id. § 355(j)(2)(A)(viii). See

infra “Section viii Statements and ‘Skinny Labels’”.

273 Id. § 355(j)(2)(A)(vii)(I)–(IV).

274 Id. § 355(j)(5)(B)(i).

275 Id. § 355(j)(5)(B)(ii).

276 Id. § 355(j)(5)(B)(iii); Caraco Pharm. Labs., Ltd. v. Novo Nordisk A/S, 566 U.S. 399, 407 (2012).

277 21 U.S.C. § 355(j)(2)(B)(i)–(iv).

278 Id. § 355(j)(5)(B)(iii).

279 Id. § 335(j)(5)(C)(i); see generally Caraco Pharm., 527 F.3d at 1285. In civil actions for patent certainty, federal

courts have subject-matter jurisdiction so long as it is “consistent with the Constitution.” 35 U.S.C. § 271(e)(5).

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while the parties litigate their patent dispute.280 If, before the expiration of the 30-month stay, the

district court concludes the patent is invalid or not infringed by the ANDA filer, FDA may

approve the ANDA as of the date of the court’s judgment or a settlement order to that effect.281 If

the court finds the patent is infringed (and the ANDA filer does not appeal that decision), then the

effective date of ANDA approval must be “not earlier than the date of the expiration of the patent

which has been infringed.”282 FDA approval of a generic drug application can thus be

significantly delayed based on patent rights asserted by the NDA holder.

Figure 1. Patent Dispute Procedures for Generic Drugs

The Hatch-Waxman Notice-and-Certification Process

Source: CRS.

280 See 21 U.S.C. § 355(j)(5)(B)(iii); Caraco Pharm., 566 U.S. at 407–08. Following amendments to the Hatch-

Waxman Act in 2003, the NDA holder may receive one 30-month stay based on patents listed in the Orange Book with

respect to an ANDA. See 21 U.S.C. § 355(c)(3)(C), (j)(5)(B)(iii); Colleen Kelly, The Balance Between Innovation and

Competition: The Hatch-Waxman Act, the 2003 Amendments, and Beyond, 66 FOOD & DRUG L.J. 417, 439 (2011)

(“[The 2003 amendments] effectively limited an innovator company to one thirty-month stay per ANDA.”).

281 21 U.S.C. § 355(j)(5)(B)(iii)(I).

282 35 U.S.C. § 271(e)(4)(A); 21 U.S.C. § 355(j)(5)(B)(iii)(II). If a judgment of infringement is appealed by the ANDA

filer and reversed by the court of appeals (i.e., the Federal Circuit), FDA may approve the application as of the date of

an appellate decision in favor of the ANDA filer. 21 U.S.C. § 355(j)(5)(B)(II)(aa)(AA).

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Orange Book Patent Listings

By statute, NDA filers must list patents that either (1) “claim[] the drug” that is the subject of the

NDA or (2) claim “a method of using such drug.”283 FDA regulations make clear that “drug

substance (active ingredient) patents, drug product (formulation and composition) patents, and

method-of-use patents” must be listed, while “[p]rocess patents, patents claiming packaging,

patents claiming metabolites, and patents claiming intermediates” must not be listed.284 As a

result, patents on a process for manufacturing a drug, for example, should not be included in the

NDA or listed in the Orange Book. (Because only certain patents relating to a drug are listed in

the Orange Book, some patent litigation concerning generic drugs takes place outside the

specialized notice-and-certification procedures of the Hatch-Waxman Act.)

FDA does not actively police the patent information listed in the Orange Book, viewing its role as

merely “ministerial.”285 This approach has raised concerns among some commentators that NDA

holders may list inapplicable patents in the Orange Book as a means to deter generic

competition.286 FDA does offer an administrative process through which “any person [who]

disputes the accuracy or relevance of patent information” in the Orange Book, or believes that an

NDA holder “has failed to submit required patent information,” may notify the Agency and seek

correction of the patent information.287 With the availability of the 30-month stay and the

requirement that ANDA filers make a certification for each patent listed in the Orange Book, it is

generally in the interest of NDA holders to list all potentially relevant patents.288 There is no

statutory provision providing that the patentee or NDA holder forfeits the right to sue if she fails

to list the applicable patents, however.289

Given the advantages of listing patents in the Orange Book and the FDA’s ministerial approach to

policing patents listed in the Orange Book, NDA holders and generic manufactures sometimes

283 21 U.S.C. § 355(b)(1). Additionally, the listed patents must be such that “a claim of patent infringement could

reasonably be asserted if a person not licensed by the owner engaged in the manufacture, use, or sale of the drug.” Id.

284 21 C.F.R. § 314.53(b)(1).

285 See Applications for FDA Approval to Market a New Drug: Patent Submission and Listing Requirements and

Application of 30-Month Stays on Approval of Abbreviated New Drug Applications Certifying That a Patent Claiming

a Drug Is Invalid or Will Not Be Infringed, 68 Fed. Reg. 36676, 36683 (June 18, 2003) (codified at 21 C.F.R. pt. 314)

(“[FDA’s] patent listing role remains ministerial.”) (citing aaiPharma Inc. v. Thompson, 296 F.3d 227, 242–43 (4th Cir.

2002)).

286 See, e.g., Eisenberg & Crane, supra note 253, at 260 (arguing that “the lack of administrative oversight” by FDA

“has allowed innovators to defer competition through the listing of irrelevant patents”). Some Members of Congress

have echoed this criticism and urged FDA to clarify the types of patents that can be listed in the Orange Book and to

enforce those guidelines. See, e.g., Letter from Sen. Elizabeth Warren and Rep. Pramila Jayapal to Dr. Robert M.

Califf, Comm’r of FDA, (Aug. 28, 2023), https://www.warren.senate.gov/imo/media/doc/

2023.08.28%20Letter%20to%20FDA%20re%20drug%20patents.pdf.

287 21 C.F.R. § 314.53(f)(1). Generally, FDA will not change the patent information in the Orange Book unless the

NDA holder amends or corrects the information in response to a patent listing dispute. Id. § 314.53(f)(1)(i); see

generally Ashley M. Winkler et al., Requirements, Benefits, and Possible Consequences of Listing Patents in the

FDA’s Orange Book, BNA PHARM. L. & INDUS. REP. 4–5 (July 3, 2018), https://www.finnegan.com/print/content/

65249/Requirements-Benefits-and-Possible-Consequences-of-Listing-Patents-in-FDAs-Orange-Book.pdf. An ANDA

filer may also make a counterclaim in patent infringement litigation to correct or delete patent information listed by the

NDA holder. 21 U.S.C. § 355(j)(5)(C)(ii)(I).

288 See Winkler et al., supra note 287, at 3 (“Having a patent listed in the Orange Book provides significant benefits to

the NDA holder.”).

289 See id. at 4–5 (discussing the “possible consequences” of not listing or late listing, including the potential loss of the

30-month stay, but not a loss of patent rights); Brian D. Coggio & Ron Vogel, Can Reference Sponsor Forfeit Right to

Sue under BPCIA?, LAW360 (July 25, 2016), https://www.law360.com/articles/820197, at n.32 (“It is worth noting that

the Hatch Waxman Act does not have a ‘list it or lose it’ provision. A patentee can choose to assert any patents listed in

the Orange Book, but it does not forfeit the right to later assert patents that were not part of the original litigation.”).

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dispute whether certain types are pharmaceutical patents were properly listed by NDA holders in

the Orange Book. For example, generic drug manufacturers have made successful legal

challenges to device patents and patents relating to risk evaluation and mitigation strategies

(REMS) as improperly included in the Orange Book.290 In 2022, FDA released a report collecting

public comments on patent information in the Orange Book and indicated that it has convened a

working group to “evaluate whether additional clarity is needed regarding the types of patents,

patent information, or other patent-related information that should be included in, or removed

from, the Orange Book, consistent with the current statutory requirements.”291

In 2023, the Federal Trade Commission (FTC) issued a policy statement concerning brand-name

drug manufacturers’ “improper listing of patents” in the Orange Book.292 The intent of the

statement was to “put market participants on notice that the FTC intends to scrutinize improper

Orange Book listings to determine whether these constitute unfair methods of competition in

violation of Section 5 of the Federal Trade Commission Act.”293 FTC observed that improperly

listed patents “may disincentivize investments in developing a competing product and increase

the risk of delayed generic and follow-on product entry, reducing patient access to more

affordable prescription drugs and increasing costs to the healthcare system.”294 A few months

later, FTC announced that it had invoked FDA’s regulatory process to challenge more than 100

patents as improperly listed in the Orange Book, including patents relating to drug-delivery

devices such as asthma inhalers and epinephrine autoinjectors.295

Section viii Statements and “Skinny Labels”

For patents that claim a method of using a drug (as opposed to a claim on the drug itself), FDA

regulations require NDA holders to include a description of listed method-of-use patents,

including information on whether the patent claims one or more FDA-approved methods of using

the drug.296 This description must be “adequate” to assist potential ANDA filers in determining

whether a listed patent covers a particular approved use or indication.297 The NDA holder must

also identify the sections of the approved drug label that describe the method(s) of use claimed by

that patent.298 FDA uses this information to create use codes for method-of-use patents, which are

290 See, e.g., Jazz Pharms. v. Avadel CNS Pharms., 60 F.4 th 1373 (Fed. Cir. 2023) (holding that patent on a computer-

implemented REMS system should not have been listed in the Orange Book because it did not claim a method of using

a drug); In re Lantus Direct Purchaser Antitrust Litig., 950 F.3d 1, 8 (1 st Cir. 2020) (holding that patent on device used

in an injector should not have been listed in Orange Book because the patent claims “do not mention the drug”).

291 FDA, Report to Congress: The Listing of Patent Information in the Orange Book ii (2022), https://www.fda.gov/

media/155200/download.

292 FTC, Federal Trade Commission Statement Concerning Brand Drug Manufacturers’ Improper Listing of Patents in

the Orange Book (Sept. 14, 2023), https://www.ftc.gov/system/files/ftc_gov/pdf/

p239900orangebookpolicystatement092023.pdf.

293 Id.

294 Id. at 4.

295 Press Release, FTC, FTC Challenges More Than 100 Patents as Improperly Listed in the FDA’s Orange Book (Nov.

7, 2023), https://www.ftc.gov/news-events/news/press-releases/2023/11/ftc-challenges-more-100-patents-improperlylisted-fdas-orange-book. Some companies have responded to the FTC’s actions by removing these patents from the

Orange Book. See Kate Goodwin, Three Companies Relent to FTC Demands, Delist Patents from FDA’s Orange Book,

BIOSPACE (Dev. 22, 2023), https://www.biospace.com/article/three-companies-relent-to-ftc-demands-delist-patentsfrom-fda-s-orange-book-/.

296 21 C.F.R. § 314.53(c)(2)(i)(O), (ii)(P)

297 See id. § 314.53(c)(2)(ii)(P)(3).

298 See id. § 314.53(c)(2)(ii)(P)(2).

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also listed in the Orange Book.299 As with all patent information in the Orange Book, FDA does

not independently verify the accuracy of use codes, but instead merely publishes the information

submitted to it by NDA holders.300

When one approved method of using the drug is still covered by a patent, but another use is

unpatented or no longer patented, the Hatch-Waxman Act allows ANDA applicants to file a

“section viii statement” instead of a paragraph I–IV certification with respect to that method-ofuse patent.301 In a section viii statement, the ANDA filer avers that it is not seeking approval for

the patented use, but only for other approved uses of the drug not covered by the patent.302 The

ANDA filer must also submit proposed labeling that omits the portions of the brand-name drug’s

label corresponding to the still-patented use.303 For this reason, generics relying on section viii

statements are said to “carve out” the patented use, resulting in a “skinny label.”304 Unlike a

paragraph III or IV certification, a section viii statement does not delay FDA’s ability to approve

the ANDA.305

Some stakeholders question whether the Hatch-Waxman Act’s skinny-label provisions are

effective in facilitating partial generic competition when some, but not all, uses of a drug are

patented. Because the FDA does not independently verify use-code accuracy, an “overly broad”

use code (and the limited ability for generics to challenge use codes) may interfere with an ANDA

applicant’s ability to use section viii statements.306 In addition, because generics relying on the

skinny-label procedure may still be sued for induced patent infringement based on the

purportedly carved out uses,307 the pathway may carry some risk for generic manufacturers.308

The BPCIA: The “Patent Dance” and Biosimilar Licensure

A different patent dispute resolution scheme applies to biological products and biosimilars, which

are subject to regulatory licensure under the PHSA, as amended by the BPCIA.309 Unlike the

Hatch-Waxman approach, FDA’s licensure of biosimilars under the BPCIA is not directly

contingent on resolution of patent disputes, and a BLA filer need not list patent information as

part of its BLA.310 Under the Purple Book Continuity Act of 2020, BLA holders are required to

299 See Caraco Pharm. Labs v. Novo Nordisk, 566 U.S. 399, 405 (2012).

300 Id. at 405–06; see generally aaiPharma Inc. v. Thompson, 296 F.3d 227, 239–41 (4th Cir. 2002).

301 21 U.S.C. § 355(b)(2)(B), (j)(2)(A)(viii).

302 Id.; see also Caraco Pharm., 566 U.S. at 406.

303 See 21 C.F.R. § 314.94(a)(8)(iv).

304 See Caraco Pharm., 566 U.S. at 406 (“If the ANDA applicant [uses section (vii)], it will propose labeling for the

generic drug that ‘carves out’ from the brand’s approved label the still-patented methods of use.”); GSK v. Teva

Pharms. USA, 7 F.4th 1320, 1328 (Fed. Cir. 2021) (using the term “skinny label”).

305 AstraZeneca LP v. Apotex, Inc., 633 F.3d 1042, 1046 (Fed. Cir. 2010).

306 See Caraco Pharm., 566 U.S. at 426–28 (Sotomayor, J., concurring); S. 1128, 118th Cong. (proposing new cause of

action to correct Orange Book use codes).

307 See GlaxoSmithKline LLC v. Teva Pharms. USA, Inc., 7 F.4 th 1320, 1338 (Fed. Cir. 2021), cert. denied sub nom.

Teva Pharms. USA, Inc. v. Glaxo-SmithKline LLC, 143 S. Ct. 2483 (2023).

308 See, e.g., Sara W. Koblitz, Ding Dong: Is the Skinny Label (Effectively) Dead?, FDA LAW BLOG (Sept. 7, 2021),

https://www.thefdalawblog.com/2021/09/ding-dong-is-the-skinny-label-effectively-dead/ (arguing that uncertainty

created by the Federal Circuit’s decision in GSK v. Teva renders the process too uncertain for a “risk-averse generic

sponsor”).

309 See supra “Biological Product and Biosimilar Licensure.”

310 See 42 U.S.C. § 262(a); Background Information: Lists of Licensed Biological Products with Reference Product

Exclusivity and Biosimilarity or Interchangeability Evaluations (Purple Book), U.S. FOOD & DRUG ADMIN. (Aug. 3,

(continued...)

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provide to FDA information on patents asserted against a biosimilar company during the so-called

“patent dance” discussed below.311 As a result, the “Purple Book”—FDA’s list of approved

biological products that is the biologics analogue of the Orange Book—contains only limited

patent information.312

Instead of the Hatch-Waxman Act’s certification process, patent disputes over biosimilars may be

resolved through the BPCIA’s patent dance.313 The patent dance is “a carefully calibrated scheme

for preparing to adjudicate, and then adjudicating, claims of infringement” by reference product

sponsors (i.e., the brand-name biologic manufacturers) against biosimilar applicants.314

Depending on their participation in the patent dance, each party has an opportunity to litigate

relevant patents in two phases. The first (“phase one”) is at the conclusion of the patent dance—

roughly six months after the biosimilar applicant files its BLA.315 The second (“phase two”) is

when the biosimilar applicant provides a notice of commercial marketing, no later than 180 days

before the date the biosimilar will be marketed.316

The first step in the patent dance process occurs when, not later than 20 days after FDA accepts a

biosimilar BLA, the biosimilar applicant provides its application to the reference product sponsor,

along with information on how the biosimilar is manufactured.317 “These disclosures enable the

[reference product] sponsor to evaluate the biosimilar for possible infringement of patents it holds

on the reference product (i.e., the corresponding biologic).”318 The biosimilar applicant and

reference product sponsor next engage in a series of back-and-forth information exchanges

regarding the patents that each party believes are relevant, as well as the parties’ positions on the

validity and infringement of those patents.319 No later than 60 days after the initial disclosure by

the biosimilar applicant, the reference product sponsor provides a list of patents that it reasonably

believes it could assert, and whether it is willing to license them.320 No later than 60 days

thereafter, the biosimilar applicant provides its factual and legal basis for why the patents are

invalid or not infringed, or whether it would accept a license.321 After the reference product

sponsor responds to the biosimilar applicant’s invalidity and infringement contentions,322 the

parties engage in “good faith negotiations” over which patents (and how many) should be

2020), https://www.fda.gov/drugs/biosimilars/background-information-list-licensed-biological-products-referenceproduct-exclusivity-and [hereinafter Purple Book Background Information].

311 Pub. L. No. 116-260, div. BB, tit. III, subtit. C, § 325(a), 134 Stat. 2936.

312 Purple Book: Lists of Licensed Biological Products with Reference Product Exclusivity and Biosimilarity or

Interchangeability Evaluations, FOOD & DRUG ADMIN. (last updated Oct. 24, 2023), https://purplebooksearch.fda.gov/

[hereinafter Purple Book].

313 See 42 U.S.C. § 262(l).

314 Sandoz Inc. v. Amgen Inc., 582 U.S. 1, 8 (2017) (holding that injunctive relief to compel participation in the patent

dance is not available under federal law); Amgen Inc. v. Sandoz Inc., 877 F.3d 1315, 1326–30 (Fed. Cir. 2017)

(holding that the BPCIA preempts state law remedies for failure to commence the patent dance).

315 Sandoz, 582 U.S. at 10.

316 Id.

317 42 U.S.C. § 262(l)(2).

318 Sandoz, 582 U.S.. at 7–9.

319 Id. at 8.

320 42 U.S.C. § 262(l)(3)(A).

321 Id. § 262(l)(3)(B)(ii)–(iii). The biosimilar applicant may also choose to supplement the reference product sponsor’s

list of relevant patents. See id. § 262(l)(3)(B)(i).

322 Id. § 262(l)(3)(C).

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litigated immediately.323 Once the parties determine the set of patents for “phase one” litigation,

the reference product sponsor has 30 days to bring an action for infringement of those patents.324

“Phase two” litigation under the BPCIA begins once the biosimilar applicant gives notice to the

reference product sponsor “not later than 180 days” before the first commercial marketing of the

biosimilar product.325 After receiving this notice, the reference product sponsor may seek a

preliminary injunction for infringement of patents that were included on its initial patent list but

not selected for phase-one litigation.326 The biosimilar applicant may choose to give this “phase

two” notice prior to FDA licensure of the biosimilar, so long as the notice is given 180 days

before commercial marketing.327 Thus, the biosimilar applicant can opt to “collapse” the two

phases of litigation, if it so chooses.328

Reference product sponsors cannot obtain injunctive relief to compel the biosimilar applicant to

engage in the patent dance.329 In practice, this limitation means that biosimilar applicants can

choose whether or not they wish to engage in the patent dance. If the biosimilar applicant chooses

not to commence the patent dance, the BPCIA “authorizes the [reference product] sponsor, but

not the applicant, to bring an immediate declaratory-judgment action for artificial [patent]

infringement.”330 Thus, although the biosimilar applicant need not immediately reveal its

manufacturing information if it chooses not to commence the patent dance, it exposes itself to an

immediate declaratory-judgment lawsuit for patent infringement.331 Biosimilar applicants thus

may face complicated strategic tradeoffs in deciding whether to initiate the patent dance.332

Unlike patent listings in the Orange Book under the Hatch-Waxman Act, the BPCIA contains an

express statutory penalty for failing to list relevant patents during the patent dance. If the

biosimilar applicant commences the patent dance, the reference product sponsor must provide a

list of all “patents for which the reference product sponsor believes a claim of patent infringement

could reasonably be asserted. . . if a person not licensed by the reference product sponsor engaged

in the making, using, offering to sell, selling, or importing [of the biological product at issue].”333

Under the “list it or lose it” requirement, the patent holder may forfeit his right to sue on patents

that are not included on this list.334 Specifically, if a patent “should have been included in the list

[as required during the patent dance], but was not timely included in such list,” then the patent

323 Id. § 262(l)(4)(A), (l)(6). The BPCIA provides a procedure for a simultaneous exchange of patent lists if the parties

cannot agree on the patents that should be litigated immediately. Id. § 262(l)(5).

324 Id. § 262(l)(6).

325 Id. § 262(l)(8)(A).

326 Id. § 262(l)(8)(B).

327 Sandoz Inc. v. Amgen Inc., 582 U.S. 1, 19 (2017).

328 See Thomas J. Sullivan, The Patent Dance, EUR. BIOPHARM. REV. 70–74 (July 2018), https://www.finnegan.com/en/

insights/articles/the-patent-dance-article.html (“A second mechanism to shorten a suit under the BPCIA would be to

collapse the two phases of litigation . . . where the biosimilar applicant provides its 180-day notice of commercial

marketing contemporaneously with its notificati

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