Since 1977, there has been no need to file for an extension of copyright to prevent it from expiring. Currently, all copyrighted works are protected for the maximum length of time set down in the copyright law.
Do I OWN the copyright?
Before can copyright or license your work, you need to make sure you actually own the copyright in it. The UC Copyright Ownership Policy, updated on February 1, 2021, is the definitive document regarding copyright ownership within the University of California.
The copyright for works created by UC students, including works created for course assignments, belongs (in most cases) to the students who created them. The rules are more complex for University of California faculty and staff. For complete information on copyright ownership at the University of California, see Works Created at UC.
It is possible, though not required, to formally register the copyright for a work you have created. Registering copyright involves paying a filing fee and submitting a copy of the work to the U.S. Copyright Office. For more details on the process, see the U.S. Copyright Office FAQ Registering a Work.
There are legal advantages to registering your copyright. Registration:
makes the facts of your copyright a public record.
provides you with a certificate of registration.
makes your work eligible for statutory damages and attorney's fees in the event of a successful lawsuit against an infringer.
is considered prima facie evidence in a court of law if the work was registered within five years of publication.
Whether or not to go to the trouble and (modest) expense of registering is up to you. If you believe you have created a work with potentially significant commercial value, then registering the copyright is a probably good idea. However, even if you don't register the copyright, any work you create is still automatically copyrighted and, therefore, protected.