Can new matter be introduced in a reissue application?

No, new matter cannot be introduced in a reissue application. This is explicitly stated in 35 U.S.C. 251(a):

“No new matter shall be introduced into the application for reissue.”

This means that the reissue application must be based on the invention disclosed in the original patent. You can’t add new inventive concepts or expand the scope of the invention beyond what was originally disclosed. The reissue process is intended to correct errors in the original patent, not to add new inventions or subject matter.

To learn more:

• reissue patent
• new matter
• patent application
• patent law