Can a reissue application filed before September 16, 2012, correct multiple errors in the original patent?

Yes, a reissue application filed before September 16, 2012, can correct multiple errors in the original patent. The MPEP 1414.02 states:

“It is not necessary to specifically state all of the errors and imperfections being corrected in the reissue application in the reissue oath/declaration. However, it is necessary to identify in the reissue oath/declaration at least one error being relied upon as the basis for reissue…”

This means that while the reissue oath or declaration must identify at least one error, it can be used to correct multiple errors in the original patent. The key requirements are:

• At least one error must be explicitly identified in the oath/declaration
• All errors being corrected must have arisen without deceptive intention
• The applicant must state that they believe the original patent to be wholly or partly inoperative or invalid

It’s important to note that additional errors can be corrected even if they are not specifically mentioned in the initial oath or declaration, as long as they meet the above criteria.

To learn more:

• reissue application
• multiple errors
• patent correction
• reissue oath
• reissue declaration