Can I perfect a foreign priority claim in a reissue application if it wasn’t perfected in the original patent?

Yes, you can perfect a foreign priority claim in a reissue application even if it wasn’t perfected in the original patent. This is one of the reasons for which a reissue application can be filed.

MPEP 1417 cites the case of Brenner v. State of Israel, which established that “reissue is also available to correct the ‘error’ in failing to take any steps to obtain the right of foreign priority under 35 U.S.C. 119(a)-(d) before the original patent was granted.”

However, if you need to make a priority claim in a reissue application that was not made in the original patent, you must:

1. File a reissue application
2. File a petition for an unintentionally delayed priority claim under 37 CFR 1.55(e)

For more information on unintentionally delayed priority claims, refer to MPEP § 214.02.

To learn more:

• foreign priority
• reissue application
• perfecting priority
• delayed priority claim