Bottom line: Under Williamson v. Citrix Online (en banc Fed. Cir. 2015), the Federal Circuit, en banc, lowered the standard back to the pre-2004 standard for when a claim limitation is to be construed as a means plus function (MPF) limitation even when the patent drafter did not intend the claim limitation to be construed as a MPF limitation, thereby increasing the odds that a claim limitation might be held invalid.
Under current U.S. patent laws, MPF limitations have certain disclosure and linking requirements in order to be held valid. As such, for those claims that are unintentionally construed as a MPF limitations, these claims are more likely to be invalid since it is doubtful that the patent drafter included language in the patent specification to meet the disclosure and linking requirements to maintain validity of the MPF claim limitation.
Previously, there was a “strong” presumption against construing a claim as a means plus function limitation if the limitation did not use the “means” term. The strong presumption was seldom rebutted. As a result, the chance that a claim that the patent drafter did not intend to be construed as a MPF limitation (i.e., by not using the “means” trigger word) would be construed as a MPF claim limitation was low. The patent drafter had a great deal of control over whether the specific claim limitation would be construed as a MPF limitation merely by choosing to include or exclude an operative trigger term “means” in the claim.
Now, after Williamson, the standard has been lowered and is now based on how a person having ordinary skill in the art (PHOSITA) would understand the claim language at issue. If the claim limitation does not include the “means” term but the PHOSITA understands the claim language to be purely functional, then the limitation is to be construed as a MPF limitation. This opens up the claim to an additional invalidity attack for being indefinite since the patent specification must disclose and link an associated structure associated with the function of the MPF limitation and it would have been less likely that the patent drafter included the required language to meet the disclosure and linking requirements.
The Williamson case is a warning that the likelihood that functional claim language will be construed as a MPF limitation against the intent of the patent drafter is now significantly greater. Also, more claims will be invalidated as being indefinite.
The Federal Circuit in lowering the standard attempted to soften the blow of this case against patent owners. The basic argument of the Federal Circuit was that the law concerning when to find a limitation to be a MPF limitation was simply thrown back to pre-2004 case law. In 2004, the Federal Circuit opined Lighting World v. Birchwood Lighting (Fed. Cir. 2004) which was the first case to raise the standard to rebut the presumption flowing from the absence of the word “means” to a strong one that is not readily overcome. Because the decision was by the entire court sitting en banc, the Williamson decision overturns the holding of Lighting World and all other cases relating to the strength of the presumption since Lighting World.
The Federal Circuit is trying to reset the clock back to 2004. However, during the past 11 years, software technology has grown significantly. Software companies relied upon the strong presumption when preparing patent applications for their inventions. Patent applications were drafted with the strong presumption in mind and used functional terms to obtain broad protection. Accordingly, this unsettles the expectation of the software patenting community by potentially invaliding software patents that would likely be upheld under the now discarded standard.
The resetting of the law back to 2004 would also appear to hurt small companies and garage shop inventors more than big companies. Thinking it through, the Williamson holding will generally cause more software claims to be construed as a means plus function claim and possibly invalidate them for being indefinite if the specification does not include any relevant algorithmic structure or link the algorithmic structure to the claims. Large companies depend on other resources than just patents to fend off competition compared to the smaller companies when launching a product. Large companies have their existing brand which they use to launch a product or service. Large companies are not as limited by monetary constraints in executing a business plan so that they can be first to market and utilize all of their distribution channels. This is untrue for smaller companies and garage shop inventor. For the smaller inventors, patent protection helps to level the playing field with the large companies. But I digress.
Now, the standard is:
whether the words of the claim are understood by persons of ordinary skill in the art to have a sufficiently definite meaning as the name for structure. When a claim term lacks the word “means,” the presumption can be overcome and §112, para. 6 will apply if the challenger demonstrates that the claim term fails to recite sufficiently definite structure for performing that function. The converse presumption remains unaffected: use of the word “means” creates a presumption that §112, para. 6 applies.
Here is where the en banc decision ends. A three member panel of the Federal Circuit went on to review the specific claim language at issue with this new lower standard in mind. In Williamson, the claim limitation at issue was a “distributed learning control module”. There was no other claim language associated with this limitation and this phrase formed the entire element. The current presumption is that this is not a means plus function limitation; however, the presumption was rebutted for the following reasons.
The Federal Circuit picked apart the language of the claim. In doing so, they indicated that the term “module” is a meaningless or nonce word and is often substituted for the word “means” thereby helping to rebut the presumption. The three judge panel also went on to explain that other words such as “mechanism,” “element,” “device” can be informally used to be equivalent to the word “means” and thus helping to rebut the presumption. These words are typically used in mechanical applications. As such, the three judge panel is signaling that this opinion is not limited solely to the software arts but is applicable to all non-software arts as well.
As for the prefix “distributed learning control”, the three member panel found that these words do not describe a sufficiently definite structure. Moreover, even though PHOSITA may be capable of building (i.e., enablement) the distributed learning control module based on the specification, this does not satisfy the written description requirement to expressly disclose structure in the patent’s specification related to the means plus function claim. Hence, the claim was found to be invalid for being indefinite.
I invite you to contact me with your patent questions. Please feel free to forward this article to your friends. As an Orange County Patent Attorney, I serve Orange County, Irvine, Los Angeles, San Diego and surrounding cities.