MPEP 1828

From Patentbarquestions

Effective July 1, 1998, applicant may correct or add a priority claim by a notice submitted to the Receiving Office or the International Bureau >(IB)< within 16 months from the priority date,

or where the priority date is changed, within 16 months from the priority date so changed, whichever period expires first, provided that a notice correcting or adding a priority claim

may in any event be submitted until the expiration of 4 months from the international filing date. PCT Rule 26bis.1 and 37 CFR 1.451 and 1.465.