United States: The Proper Role For The Presumption Of Validity

Last Updated: July 2 2014
Article by Derek F. Dahlgren

In 2011, the Supreme Court addressed the presumption of validity in Microsoft Corp. v. i4i Limited Partnership, 131 S. Ct. 2238 (2011). It confirmed that the standard of proof for invalidity is clear and convincing evidence. Initially, this opinion was seen by many as preserving the strength of patents. But closer scrutiny reveals that the Supreme Court’s analysis does not extend to all invalidity defenses. According to Justice Breyer’s concurrence, joined by Justices Scalia and Alito, the presumption of validity only provides protection against factual elements of an invalidity challenge. That concurrence, and the Supreme Court’s recent opinion in Nautilus, Inc. v. Biosig Instruments, Inc., suggest that the presumption of validity has no application to purely legal bases for invalidity.

A brief discussion of i4i and Nautilus is instructive. In i4i, Microsoft appealed a jury decision finding that it had not proven invalidity due to the on-sale bar, a purely factual inquiry, by clear and convincing evidence. On appeal, Microsoft argued that a defendant to an infringement action need only persuade the jury of an invalidity defense by a preponderance of the evidence. The Supreme Court rejected that argument.

Instead, the Supreme Court concluded that the presumption of validity codified the pre-1952 standard set forth in opinions such as Radio Corp. v. Radio Laboratories, 293 U.S. 1 (1934). The Supreme Court stated that by the time Congress enacted § 282, “the presumption encompassed not only an allocation of the burden of proof but also an imposition of a heightened standard of proof.” i4i, 131 S. Ct. at 2246. The Supreme then upheld the Federal Circuit’s articulation that “a defendant seeking to overcome [the presumption of validity] must persuade the factfinder of its invalidity defense by clear and convincing evidence.” Id. at 2243.

Justice Breyer wrote a separate concurrence. There, he stated “I believe it worth emphasizing that in this area of law as in others the evidentiary standard of proof applies to questions of fact and not to questions of law.” Id. at 2253. He also noted:

Many claims of invalidity rest, however, not upon factual disputes but upon how the law applies to facts as given . . . Where the ultimate question of patent validity turns on the correct answer to legal questions—what these subsidiary legal standards mean or how they apply to the facts as given—today’s strict standard of proof has no application.


In Nautilus, the same issue—the application of the presumption of validity—arose at oral argument. During the argument, Justice Kennedy pressed Nautilus’ counsel on how the presumption of validity applies to indefiniteness. Nautilus’ counsel conceded that the presumption of validity would accord deference to the PTO’s fact-finding. Tr. at 19:22 – 21:8. But he stated that since there were no fact-findings at issue in this case, the presumption did not apply. Id. At Justice Kennedy’s prompting, he also agreed that the PTO’s legal decisions are not accorded any deference. Id. at 21:4-8.

On June 2, 2014, the Supreme Court issued its opinion in Nautilus, and again touched on the issue. In footnote 10, the Supreme Court rejected the idea that a permissive definiteness standard accords with the presumption of validity. Slip Op. at 13 n.10. To the contrary, it stated that the presumption does not alter the degree of clarity that § 112, ¶2 requires. Id. That said, the Supreme Court ultimately did not address the parties’ dispute as to whether subsidiary factual issues trigger the clear-and-convincing evidence standard. Id. Because the Federal Circuit treated indefiniteness as a legal issue reviewed without deference, and the parties had not identified any contested factual matter, Supreme Court concluded the question could be settled another day. Id.

So where does that leave us? While the Supreme Court has not expressly held that the presumption of validity has no role in purely legal validity challenges, it certainly makes sense. According to i4i, the presumption of validity serves two functions: allocating the burden of proof and imposing the standard of proof. 131 S. Ct. at 2246. For a purely legal question, however, there is nothing to prove by clear and convincing evidence. Furthermore, to apply the presumption for a legal challenge would give deference to the PTO’s legal conclusions. The Federal Circuit does not do that. And the PTO lacks substantive rule-making authority, at least with respect to defining the metes and bounds of invalidity defenses. Thus, there does not appear to be any basis for according deference to the PTO’s legal conclusions. Consequently, for pure questions of law, it seems reasonable to conclude that the presumption of validity has absolutely no bearing. And as a result, invalidity challenges based on purely legal grounds may be much more powerful.

Nonetheless, while the Supreme Court may have circumscribed the application of the presumption of validity, it now has the opportunity to reject the assertion that claim construction is a pure question of law. See Teva Pharms. USA, Inc. v. Sandoz, Inc., No. 13-854. The Supreme Court hinted in Nautilus that factual questions permeate claim construction when it cited to Markman and stated that claim construction “may turn on evaluations of expert testimony.” Nautilus, slip op. at 11. Should that become settled law after Teva, one likely consequence would be a resurgence of the presumption in areas previously considered purely legal domains. Generally, the pure legal bases for invalidity are premised on the notion that claim construction is a pure question of law. Therefore, while the Supreme Court may have given patent challengers a gift in i4i and Nautilus, it could be short-lived to a certain degree.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.

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Derek F. Dahlgren
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