What are the advantages of filing a priority patent in one country before filing a patent for that same invention in a number of other countries?

Lawyer

Dear Madam, Dear Sir,

When you file a patent application in a country, you have a period of one year, under priority of your first filing, to extend the protection for your invention in other countries if these ones are members of the Union Convention of Paris (1883). This system was put in place to prevent the Patent and Trademark Office of the second filing (eg WIPO) objects you subsequently the disclosure of your own invention because of the first filing and thus the absence of novelty of your invention and the impossibility of its patenting legally speaking.

This priority system has three advantages:

- First and foremost, you avoid getting "self-anteriority" by disclosing your invention (some countries such as the USA and Canada still permit under certain conditions the disclosure on their national territory before the filing before their Offices). Your second filing will be well operated "under priority" of the first filing and benefit from the date of the first one. The prior art to be considered in assessing the patentability of the second filing (for example, a PCT international application) will be the art of the first filing (for example, a US patent). That is why we call this the "unionist priority";

- Also and for the same reasons, avoid objections based on the same or similar inventions that could potentially be filed in the interim between the first and second filing ;

- Finally, you have exactly one year after the first filing "to go to the other countries" and extend the protection for your invention abroad which leaves you material time to enjoy the patentability of your invention in the original country (official research report, legal opinion from your patent attorney ...) and to follow or not the filing patent prosecution, to reflect on the commercial potential in other countries and to select those that are more interesting in this regard or where counterfeiting is most effectively sued and punished (that are called "countries of interest"), to raise additional funds to find future industrial and commercial partners too ...

Because of this priority for a year you do not need to file simultaneously the same invention in several countries since in any case, the second filing has been made under the first priority and so will have the filing date of the first filing.

I hope that things are now clearer for you.
Do not hesitate to revert to me should you need further details.

Your sincerely,
Simon

Patent Attorney

You don't actually file a "priority" patent (application) in one country before filing a patent application in another country - the patent application that you file in your first country automatically becomes your priority patent application. Many/most countries require the filing of a patent application in the country where the invention was first developed before they will permit patent applications to be filed in foreign countries, and then once the first patent application is filed, you have one year to file in foreign countries or PCT in order to claim priority back to that first patent application.