What must an applicant do if the second-filed application discloses but does not claim the same subject matter as a prior application?

The correct approach when a second-filed application discloses but does not claim the same subject matter as a prior application is to file an affidavit showing derivation. This is important because the U.S. patent system has rules regarding the priority of claims and the disclosure of previously filed applications. When a subsequent application contains disclosures that relate to or stem from an earlier application, it is crucial that the applicant establishes the connection between the two to avoid potential issues regarding inventorship and rights to the invention.

Filing an affidavit serves as an official statement that verifies the relationship between the applications, helping to clarify the derivation of the invention and affirming the applicant's rightful entitlement to claim it. The affidavit acts as evidence to the patent office regarding the originality of claims made in the second application, ensuring that the rights over inventions are appropriately allocated.

Each of the other options does not adequately address the situation where the second application discloses but doesn’t claim the same subject matter. For instance, filing a petition for a derivation proceeding is unnecessary unless there are competing claims regarding who originally created the invention. Claiming a new invention altogether may not be relevant if the second application is meant to build upon or expand upon the ideas in the first application. Abandon