Foreign patent traps

Outside of the US, foreign patent offices will often use your own prior patent filings against you.  Avoid this trap by planning carefully.

Both US and foreign patent laws are based on various legal fictions.  One legal fiction is that an invention is instantly created in a fully formed state.  Another legal fiction obviousness. A particular improvement to the invention may not have been obvious to you, the real inventor. But, a foreign examiner can reject your improvement as obvious to an imaginary “person of ordinary skill in the art”.  Patent law just doesn’t cope with hindsight well.

In practice, we all know that real inventions often come into life slowly, usually after much trial and error.  Complex inventions may take years to fully develop. You are thus faced with a dilemma – file fast so as to be the first person to file? Keep working on the invention, file a better patent application, but possibly lose to someone who filed sooner?

US patent laws recognize this problem. The US allows an inventor to file as many patent applications as needed, even over a period of years. So in the US, you can gradually accumulate a “stack” of patent applications.  This stack of patent applications lets you capture the time of earliest invention. This also lets you capture a later, time-optimized, form of the invention. Intuitively this system seems fair.  Wouldn’t it be unfair to use an inventor’s own earlier work against the inventor?

Doesn’t this basic rule of fairness apply everywhere?  Unfortunately, it does not.  The harsh reality is that in international patent filings outside of the US, your own earlier patent applications are used against you.

Inventors and startups are often trapped by this assumption of basic fairness. 

Here the only way to avoid the trap is to recognize that this problem exists. You need to take steps to mitigate problems.

After you file your US application, assume you have at most a 12-month window to make further improvements. Plan accordingly. Submit your improvements as an updated PCT patent application before the 12 month anniversary of your first patent application.

After 12 months, you can’t claim the priority date of your first US filing. Someone else can jump ahead of you and claim credit.  Even worse, after 18 months, foreign examiners can use your first US patent application against your later filed improvement.

It is very irritating to have a foreign examiner claim that your improved invention is obvious against your earlier-filed application.  Even more irritating when you know that in reality, the improvement was totally not obvious.  Perhaps the improvement may have taken you a year or more of hard work!  Too bad — to the foreign examiner, your improvement is obvious.

The lesson here is: if you have made improvements, file them as an updated international patent within 12 months of the filing date of your first invention (or in an emergency, at least before your first patent application is published — usually 18 months after first filing).