Yes. Failing to include an appropriate AI disclosure in an application for registration to the U.S. Copyright Office when required can lead to cancellation of registration or potential legal challenges to the validity of the copyright. The U.S. Copyright Office can cancel or modify a registration if it discovers undisclosed AI use, and it has done so on occasion. Even if the Copyright Office does not cancel the registration, a court may disregard a registration and refuse to enforce a copyright if it determines that a required AI disclosure was not made.