Good Faith but Mistaken Belief in Invalidity Combined with Good Faith but Mistaken Belief in Infringement…

At the biosimilars conference last week, everyone was puzzled about whether you could be liable for inducement if you had a good faith belief that a patent was invalid but the patent was valid.  That seems to be the law, right now at least, pending Commil.  (Dennis’s write up is here, along with a link to the CAFC decision.)  I think Commil’s wrong for a lot of reasons, but…

Let’s have some fun on Saturday morning and combine it with Frolow (Dennis’s post here.)  Suppose I mark a product as patented, but I’m wrong: although I in good faith marked it, it doesn’t meet the limitations of a claim.  (Obviously, this could occur for various reasons, including manufacturing tolerances.)

So, now let’s say someone is sued for inducing manufacture of the product.  If they’re wrong about infringement, under Frolow, the fact of marking, alone, is enough evidence to get to the jury on literal infringement.  Under Commil, it seems that a mistaken belief in invalidity is also enough to get to the jury, on non-infringement.

So, you could end up with someone (a) in fact not infringing (b) a valid patent, but liable for infringing it because she mistakenly thought she was infringing it.  You could also end up with someone (a) infringing by inducement (b) a valid patent, but not being liable for inducing infringement because she mistakenly thought the patent was invalid.


About David

Professor of Law, Mercer University School of Law. Formerly Of Counsel, Taylor English Duma, LLP and in 2012-13, judicial clerk to Chief Judge Rader.

2 thoughts on “Good Faith but Mistaken Belief in Invalidity Combined with Good Faith but Mistaken Belief in Infringement…

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    What happened in Wilson was the licensee mistakenly marked products. So, the patentee was “innocent,” I guess (can’t believe it would affect the patent).

    Read the Frolow case. Your head will spin.

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    If the product is incorrectly marked I am not sure the patent is even enforceable. See the Milgo cases where marking a product that did not have a feature that was argued to a court was deemed to be fraud on the court. No one even thought to bother to inquire into whether the products were incorrectly marked by mistake or otherwise.

    So, do not think inducement can depend or not on whether the products were marked incorrectly. But the enforceability of the patent my so depend.

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