According to the USPTO 37 C.F.R. 1.45 Application for patent by joint inventors, you can apply for joint inventorship provided you have contributed in the development of the patent and each inventors must make an inventor's oath or declaration as required by Section 1.63. Inventors can apply for a joint patent even though:

(1) They did not physically work together or at the same time; (2) Each inventor did not make the same type or amount of contribution; or (3) Each inventor did not make a contribution to the subject matter of every claim of the application.

If the author did not include you and your co-worker as an inventor of the patent, you have the right to file a case against the author. Ask an expert for the right thing to do in such situation.

According to the USPTO 37 C.F.R. 1.45 Application for patent by joint inventors, you can apply for joint inventorship provided you have contributed in the development of the patent and each inventors must make an inventor's oath or declaration as required by Section 1.63. Inventors can apply for a joint patent even though:

(1) They did not physically work together or at the same time; (2) Each inventor did not make the same type or amount of contribution; or (3) Each inventor did not make a contribution to the subject matter of every claim of the application.

If you fit the definition of a co-inventor and the applicant did not include you and your co-worker as an inventor of the patent, you might have the right to file a case against the applicant. Ask an expert for the right thing to do in such situation.