A PCT Application for a Patent of Addition?

A few days back, a friend of mine, who is a very keen student of the law of Patents, asked me an interesting question which hadn’t occurred to me earlier. Her question was-

“Is it possible to file a PCT application for a patent of addition?”

My answer was a yes, but I thought I might as well back the answer with proper research. So here it goes.

Let’s begin with the “Definitions” under Article 2 of the Patent Co-operation Treaty (PCT). The relevant definitions to be looked into are those of “application” and “patent” under sub-article (i) and (ii) of Article 2. For ease of reference, following are the definitions:

(i) “application” means an application for the protection of an invention; references to an “application” shall be construed as references to applications for patents for inventions, inventors’ certificates, utility certificates, utility models, patents or certificates of addition, inventors’ certificates of addition, and utility certificates of addition;

(ii) references to a “patent” shall be construed as references to patents for inventions, inventors’ certificates, utility certificates, utility models, patents or certificates of addition, inventors’ certificates of addition, and utility certificates of addition;

I think the above definitions make it crystal clear that a patent of addition too can be the subject-matter of a PCT application. But then, what about priority dates? A patent of addition, in my opinion, cannot be filed beyond the standard 12-month window provided under the law, if it seeks the benefit of priority of the basic parent application.

This applies to 2 situations- the first where the basic application is an application filed in a national patent office and the PCT application takes benefit of the basic application; the second is where the basic application is itself a PCT application. After all, a PCT application can take priority from an earlier filed PCT application.

The question now to be answered is what happens if a person wishes to file a PCT application beyond the 12 month period of the earlier filed PCT application? The answer could be that such an application may be filed because non-publication of the parent PCT application does not deprive it of its novelty.

That said, since it cannot and hence does not take benefit of the parent PCT application, it may be treated as an independent PCT application, and not as a patent of addition. If so, it may fall short on the criterion of non-obviousness, because it will now be judged against the invention disclosed in the parent PCT application as well.

However, this does not prevent filing of applications for patents of addition from the national phase applications because there is no time-limit under national regimes (atleast in India) for filing of a patent of addition. 

Corrections are welcome!