Back when I was losing on False Patent Marking.

Proof of objective facts and subjective intent are essential to success on a false patent marking claim (as well as on the inequitable conduct defense).  Showing that ‘patented’ was in some form marked on a product should not be hard.  In all ‘false’ conduct actions, the most difficult aspect is proving intent.

In a case some years past, the Judge issued fairly straightforward rulings that “intent” raised fact questions precluding summary judgment on a false patent marking claim. The court noted that the product was promoted as “patented” before an application had been filed, and that notice of the misidentification was received, also before the patent application was filed. The one promoting it may have believed it was patented. 

Seemed plain – accepting favorably an inference of ‘good faith’  despite a mistaken belief that the product was “patented.”  This did not spawn hordes of mismarking cases, and intent should remain difficult to prove.