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The Circle Bastiat

Intellectual Property 101: How to get – and challenge – a patent

As the Supreme Court prepares to cut the 'clear and convincing' standard for proving patent invalidity, it's worth examining the key steps of the patent process.

By Stephan KinsellaGuest blogger / December 3, 2010

The U.S. Patent and Trademark Office (PTO) in Alexandria, Va., as seen in June 2009. To obtain a patent, applicants must file an application with the PTO, including all relevant 'prior art,' or existing patents for similar products. If the PTO concludes that the new invention is sufficiently different from the items in the prior art, a patent can be granted.

Olivier Douliery / Abaca Press / MCT / File


Peter Zura, in the 271 Patent Blog, notes, in Supreme Court Prepares to Chop Down “Clear and Convincing” Standard for Proving Patent Invalidity, that the Court has agreed to hear the appeal of the Microsoft Corp. v. i4i Ltd., case. In this case, i4i sued Microsoft for patent infringement and was awarded a $290M judgment, based on Microsoft’s use of XML in Word.

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At issue here is the burden of proof Microsoft needs to satisfy to prove i4i’s patents invalid. Let me try to explain without getting overly legally technical. When a patent application is filed, the applicant is supposed to submit all the material prior art he is aware of. The patent office Examiner also does a search to try to find other prior art. He or she then examines the patent application in light of the prior art that is submitted and that found by the Examiner. If a patent eventually issues, then it is said to have a “presumption of validity”. A defendant can argue that the PTO made a mistake and “should not” have issued the patent–say, because it was obvious in view of some prior art–but he has the burden of proof–but it’s an uphill battle. If the defendant argues that the patent is obvious in view of prior art that the Examiner already considered (or that is similar to–cumulative with–prior art considered by the Examiner), then it’s even harder. If he finds prior art totally different from what the Examiner considered, maybe it’s easier to argue–you don’t have to argue the Examiner made a mistake, just that he didn’t see certain prior art.

Now, when you have the burden of proof there are various standards of proof, to-wit: preponderance of the evidence (more likely than not) and “beyond a reasonable doubt”, at two ends of the spectrum; with “clear and convincing evidence” being somewhere between. The question Microsoft put to the Supreme Court was which standard should be used to consider a patent’s validity, when there is new prior art submitted that has not yet been considered. If the Court says preponderance is sufficient (as they seem likely to do), this makes slightly easier to challenge a patent’s validity, in some situations (where prior art is found that is not the same as or cumulative to the prior art the Examiner considered). But the defendant still has the burden of proof; the patent is still presumed valid. And the defendant is going to make the same arguments for invalidity. It’s probably very rare when a given defendant in a given patent infringement suit would lose based on the C&C standard but win on the preponderance standard; these standards are not exact and a judge swayed by an argument for invalidity (or not) is likely to usually have the same conclusion regardless of the standard of proof.

Now, I hope the Court does side with Microsoft. This would be minor improvement in the law. Not a major one at all–the patent is still presumed valid; the defendant still has the burden of proving it invalid; the burden would be slightly less difficult to satisfy, but only in a narrow subset of cases where the argument is not that the Examiner made a mistake (failing to realize the patent was too similar to the prior art he considered) but that the Examiner didn’t have the relevant prior art in front of him. But it would be a good change–which is why I proposed in an earlier article, “Reducing the Cost of IP Law,” that the patent law be revised to “Remove the presumption of validity that issued patents enjoy.” That would be a real change, and a much better one than merely reducing one vague standard of proof to a slightly lower one in a narrow set of cases.