How is the effective filing date determined for continuation and divisional applications?

For continuation and divisional applications, the effective filing date is determined as follows:

If the application is a continuation or divisional of one or more earlier U.S. applications or international applications and if the requirements of 35 U.S.C. 120, 365(c), or 386(c) have been satisfied, the effective filing date of a claimed invention is the same as the earliest filing date in the line of continuation or divisional applications.

This means that if the requirements for claiming benefit to an earlier application are met, the claimed invention in a continuation or divisional application can have an effective filing date that is earlier than its actual filing date, potentially reaching back to the earliest application in the chain.

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Topics: MPEP 2100 - Patentability, MPEP 2152.01 - Effective Filing Date Of The Claimed Invention, Patent Law, Patent Procedure
Tags: continuation application, Divisional application, effective filing date, Priority Claim