Where To Enter The PCT National Phase?

Just about anywhere in the world is where one may claim a patent with an international PCT patent application. There are, after all, 154 countries bound by the Patent Cooperation Treaty (PCT).¹ But almost no one, except well-heeled pharmaceutical companies, files in every last one. That is, when companies have to start spending real money to enter the PCT national phase at the 2½ year (30 month) deadline, they trim their choices way down.

What is remarkable is that those choices tend to be the same countries, at least for U.S.-origin PCT applications. U.S.-origin PCT applications are those with a "US" in the international application number, such as PCT/USxx/xxxxx.² This is true even though there is a veritable laundry list of considerations that companies presumably analyze for each and every patent application.