What is required to claim foreign priority under 35 USC 119(a)?

To claim foreign priority under 35 USC 119(a), it is essential that a U.S. application is filed based on an earlier foreign application, and at least one inventor must be a U.S. inventor named in the application. This requirement ensures that there is a connection to the U.S. patent system, allowing for the rights and protections afforded by U.S. law to be invoked for the invention initially disclosed in the foreign application.

The priority claim is meant to establish that the invention disclosed in the U.S. application has the benefit of the filing date of the earlier foreign application. The presence of at least one U.S. inventor serves to establish eligibility for this privilege. The priority claim is not contingent upon the residency of all inventors or the necessity of multiple inventors sharing commonality between the applications. Rather, the critical factor is the existence of the foreign application and naming at least one U.S. inventor in the subsequent filing.

This emphasis on having a U.S. inventor allows for a practical link to the U.S. jurisdiction, ensuring that the inventor can take advantage of the specific protections and advantages provided under U.S. patent laws.