What happens if a claim for foreign priority is presented after the time period set in 37 CFR 1.55?
If a claim for foreign priority is presented after the time period set in 37 CFR 1.55, the claim may be accepted if it is accompanied by a grantable petition to accept the unintentionally delayed claim for priority.
In addition, a petition to accept an unintentionally delayed claim for foreign priority is necessary to correct any error in a foreign priority claim if the correction is sought after expiration of the time period set forth in 37 CFR 1.55.
The answer to this question can be found in chapter 200 of the MPEP. This chapter covers Types, Cross-Noting, and Status of Application.
The answer is from the 9th Edition, Revision 10.2019. Depending on future changes to the MPEP, the question and answer may or may not be applicable in later Editions or revisions.
This question and answer come from section 214.02 of the MPEP. The following is a brief summary of section 214.02.
214.02 Unintentionally Delayed Priority Claims
If a claim for foreign priority is presented after the time period set in 37 CFR 1.55, the claim may be accepted if the priority claim was unintentionally delayed. This section presents further details on unintentionally delayed priority claims.