A patent is considered personal property in California, and as such, you can transfer its ownership to another person. According to the United States Patent and Trademark Office, this transfer of ownership is called patent assignment. You have the ability to assign ownership of part of your patent or all of it to someone else as long as it is done in writing and recorded with the USPTO within three months. This document must also be witnessed by an approved official.
In order to record the assignment with the USPTO, you will need to do one of two things. You will either need to make the assignment in the patent file or in the assignment records. Making the record in the assignment records does not necessarily give the new owner all rights and serves only as a public notice. So, in order for the new owner to really have all the rights to the patent, it needs to be recorded in the patent file.
There are other ways to share ownership of a patent or allow someone else to use your patent without losing your rights to it. For example, a patent can be owned by more than one person as long as the ownership is stated in the original patent application. Allowing others to use your patent is called licensing. This is not the same things as assignment, though. With a license, you are giving someone the right to use your patent but not assigning them ownership of the patent. Typically, a license will involve restrictions, such as the length of time the licensee can use the patent. This is general information only and is not intended to provide legal advice