The owner of a U.S. patent can stop anyone from making, using, selling, or offering for sale the invention in the United States. In addition, a U.S. patent owner can stop anyone from importing unauthorized copies of the invention into the U.S. However, U.S. patent rights stop at the American border. An inventor cannot use a U.S. patent to stop someone from making, selling, or using the invention in another country. To do that, American inventors must acquire patent rights in that country and rely on rules of reciprocity in international treaties.
“Reciprocity” or “reciprocal treatment” means that when an inventor from Country A applies for a patent in Country B, the inventor will be treated in the same manner as inventors living in Country B. This reciprocal treatment extends only to inventors who live in nations that have signed the treaty (“signatory nations”). The U.S. is a signatory nation to several international patent treaties, the most important of which are the Paris Convention and the Patent Cooperation Treaty.
The U.S., like the majority of industrialized nations, is a party to the Paris Convention, an international treaty that provides reciprocal patent filing rights. Members of the Paris Convention are known as Convention countries. In order to acquire patent rights, the inventor must separately file a patent application in each Convention country. The advantage of the Paris Convention for a U.S. inventor is that the inventor’s filing date can be retained in another Convention country provided that the patent application is filed in the country within one year of the U.S. filing date (or six months for design patents). For example, an inventor files her U.S. patent application on May 1, 2011. If the inventor files a patent application in Canada before May 1, 2012, she will have priority over any other patents that may have been filed after May 1, 2011.
A U.S. inventor filing in non-Convention countries must file the foreign application before publishing or selling the invention. This is because, unlike the U.S., virtually no foreign country provides a one-year grace period (a feature of American patent law that will eventually disappear with the passage of the America Invents Act). Thus, any publication or sale of the invention is fatal in foreign countries.
Most industrialized countries are also members of the PCT, a treaty that enables inventors to file a relatively economical international application in their home country within one year of their home country filing date. There are two advantages in filing a PCT application: the inventor obtains a filing date that is good in every member country in which the inventor seeks patent protection; and an initial international patent search will be conducted and PCT member countries will rely heavily on this search. The inventor in a PCT nation must eventually file separate “national” applications in each country or group of countries (such as the EPO) where the inventor wants coverage, but the initial search procedure simplifies the international patent process.
A U.S. inventor cannot file a foreign patent application until the inventor gets a PCT foreign-filing license or until six months have elapsed from the inventor’s U.S. filing date. The inventor can then obtain a 20 or 30-month delay, depending on whether the inventor requests examination (a provision known as “Chapter II”) before filing in countries that belong to the PCT. In the following sections we will discuss these treaties and related international rules in more detail.
Patent prosecution and practice in other countries is relatively complicated and extremely expensive. It is usually only worthwhile for U.S. inventors to file applications in a foreign country if a significant market for the invention is very likely to exist, or the inventor has a foreign licensee (someone who’s paying the inventor for the invention and know-how). Otherwise, the cost of acquiring foreign patent protection may exceed the potential returns from sales of the invention. The fact that an infringement occurs in a country does not always justify filing in that country. Usually, it pays to file only if the infringement is substantial enough to justify the expense of filing, getting the patent, and the uncertainties of licensing and litigation.
Portions of this article are derived from Nolo's Patents for Beginners.