15 March deadline for keeping possible advantages of old US patent rules

12 February 2013


US patents/applications with an effective filing date of 16 March 2013 or later will be treated under the new provisions of the America Invents Act ("AIA"), which brings in a form of "first inventor to file" regime. US patents/applications with an effective filing date earlier than 16 March 2013 will be treated under the previous "first to invent" provisions. There may be advantages to a patent/application being considered under the previous provisions, for example because of the differences between the rules concerning what is considered prior art for a particular patent/application. This may be particularly important if you are working in a very competitive technical area.

To benefit from the existing rules, the priority date of the patent must fall before 16 March 2013 or, if there is no priority claim (or the priority claim is invalid), the filing date must fall before that date. For an ex-PCT US application, the relevant filing date is the PCT filing date, not the date of entering the national phase in the US.

So, if you are filing a new application without claiming priority, it may be desirable to file the application before 16 March 2013, if there is any intention of ultimately proceeding in the US.

If you are filing a PCT or direct US application claiming priority from an application with a priority date after 15 March 2012, it may be useful to file the priority-claiming application earlier than the end of the priority year in order to get a filing date that is also before 16 March 2013. This may be particularly useful if you wish to include additional subject matter in the priority-claiming application.

In each case, the possible benefits of getting an effective filing date earlier than 16 March 2013 have to be balanced against possible drawbacks of filing earlier than you would otherwise choose to do so, such as loss of patent term or less advanced experimental work.


Please get in touch as soon as possible with your usual Potter Clarkson contact for further information, particularly if you may want to file an application before 16 March 2013.

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