# MPEP § 901.05(a): Citation Data

> Federal · Agency guidance · In force

URL: https://www.frixlaw.com/law-library/statutes/MPEP_S901.05(a)

## Section

- **Citation:** MPEP § 901.05(a)
- **Heading:** Citation Data
- **Jurisdiction:** Federal
- **Kind:** Agency guidance
- **Status:** In force
- **Text as of:** August 14, 2026
- **Source:** Compiled text
- **Location:** USPTO MPEP / Chapter 0900 - Prior Art, Search, Classification, and Routing / MPEP § 901.05(a)

## Text

Foreign patent publications that use Arabic and Roman numerals in
lieu of names to indicate the date show in order the day, month, and year, or
alternatively, the year, month, and day. Roman numerals always refer to the
month.
Japanese patent application publications show the date in Arabic
numerals by indicating in order the year of the reign of the Emperor, the month, and
the day. To convert the Japanese year of the Emperor to the Western calendar year,
for years prior to 1989, add 1925 to the JAPANESE YEAR. For example: 40.3.6 = March
6, 1965. For years after 1988, add 1988 to the JAPANESE YEAR.

## Nearby sections

- [MPEP § 901 Prior Art](https://www.frixlaw.com/law-library/statutes/MPEP_S901.md)
- [MPEP § 901.01 Canceled Matter in U.S. Patent Files](https://www.frixlaw.com/law-library/statutes/MPEP_S901.01.md)
- [MPEP § 901.01(a) Ordering of Patented and Abandoned Provisional and Nonprovisional Application Files](https://www.frixlaw.com/law-library/statutes/MPEP_S901.01(a).md)
- [MPEP § 901.02 Abandoned Applications](https://www.frixlaw.com/law-library/statutes/MPEP_S901.02.md)
- [MPEP § 901.03 Pending Applications](https://www.frixlaw.com/law-library/statutes/MPEP_S901.03.md)
- [MPEP § 901.04 U.S. Patents](https://www.frixlaw.com/law-library/statutes/MPEP_S901.04.md)
- [MPEP § 901.04(a) Kind Codes](https://www.frixlaw.com/law-library/statutes/MPEP_S901.04(a).md)
- [MPEP § 901.05 Foreign Patent Documents](https://www.frixlaw.com/law-library/statutes/MPEP_S901.05.md)
- [MPEP § 901.05(a) Citation Data](https://www.frixlaw.com/law-library/statutes/MPEP_S901.05(a).md)
- [MPEP § 901.05(b) Other Significant Data](https://www.frixlaw.com/law-library/statutes/MPEP_S901.05(b).md)
- [MPEP § 901.05(c) Obtaining Copies](https://www.frixlaw.com/law-library/statutes/MPEP_S901.05(c).md)
- [MPEP § 901.05(d) Translation](https://www.frixlaw.com/law-library/statutes/MPEP_S901.05(d).md)
- [MPEP § 901.06 Nonpatent Publications](https://www.frixlaw.com/law-library/statutes/MPEP_S901.06.md)
- [MPEP § 901.06(a) Scientific and Technical Information Center (STIC)](https://www.frixlaw.com/law-library/statutes/MPEP_S901.06(a).md)

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Source: Frix Law Library, https://www.frixlaw.com/law-library/statutes/MPEP_S901.05(a). Check the current official text before relying on it. Not legal advice.