A Decision Guide For Filing International Patent Applications For Multiple Inventions

Companies have two choices for meeting the PCT patent application filing requirements when they have multiple pending provisional applications. We go through the pros and cons for each approach.

A company engaged in research and development will often create multiple related inventions within a year, and file a separate provisional application for each invention within that year. To obtain patent protection internationally for those inventions, the company must then file a PCT application for each invention within one year of the provisional application filing. The company has a choice to (a) file one PCT application that describes all of the inventions within one year of the earliest provisional application, or (b) file a separate PCT application for each invention within one year of each provisional application. There are advantages and disadvantages for each approach.

For example, a company files provisional applications on January 1 and November 1, 2017, describing two different but related inventions. The company can then (a) file one PCT application by January 1, 2018 that describes both inventions, or (b) file two separate PCT applications, by January 1, 2018 and November 1, 2018, each only describing one invention. Here are the advantages and disadvantages of filing one PCT application on January 1, 2018 that describes both inventions, rather than filing two separate PCT applications, each describing only one invention, on January 1, 2018 and November 1, 2018.

Advantages of filing one application that describes both inventions

Save filing fees

By filing one application that describes both inventions, the company saves money by only paying one filing fee, rather than fees for two PCT applications. Although the PCT will only normally provide a search on one of the inventions, the company can pay a fee to have both inventions searched.

Flexibility to pursue either or both inventions

If the company ends up developing only one of the two inventions, that invention can be pursued with this application; there will not be a second "wasted" application that is of no interest to the company.

Establish that the two inventions lack unity of invention

When both inventions are listed in the PCT application, the examining patent office will decide whether the two inventions are different enough from each other that one invention is patentably distinct from the other invention. This can be important if there is prior art that describes one of the...