As patent prosecution professionals, we are all familiar with the sometimes vexing challenge of responding to examiner rejections, particularly when those rejections hinge on claims of “common knowledge.” While examiners may sometimes invoke this term to support an obviousness argument or to make the obviousness rejection seem even more daunting to overcome, patent professionals should recognize that the MPEP (Manual of Patent Examining Procedure) has strict rules for how "common knowledge" must be substantiated. Misusing or overstating such claims can actually work against an examiner's argument, and understanding how to counter these assertions can turn lemons into lemonade (or as shown below, turning pieces of meat into a target comminuted meat product having a target lean point for your grilling pleasure).
Specifically, patent examiners often invoke terms like “common” or “well-known” when making obviousness rejections. For example, an examiner may argue that certain features in the prior art are “commonly included” in a particular field of technology, thereby implying that such features would have been obvious to a person of ordinary skill in the art (POSITA). However, such statements, if not supported by evidence, do not carry the weight the examiner might intend. In fact, the MPEP specifically requires examiners to substantiate any assertion of common knowledge with concrete evidence. And that evidence has to be more than that the asserted feature was known - the evidence must actually support the idea that it was common. As set forth in MPEP § 2144.03, which discusses the need for “Objective Evidence of Obviousness,” the Office must provide factual evidence to back up any claims regarding what constitutes common knowledge. Simply stating that a feature is “common” or “well-known” is not sufficient to justify a rejection. The examiner must show that the feature was, in fact, widely known and understood within the field at the time of invention.
Moreover, MPEP § 2144.03 clarifies that an examiner must explain how the common knowledge in the art is reflected in the cited references, not just make sweeping claims. Any assertion that relies solely on “common knowledge” must be carefully backed by tangible evidence, whether that be in the form of prior art that explicitly supports the assertion, or other verifiable sources.
A recent PTAB decision (17/963,407) illustrates just how important it is for examiners to substantiate claims of common knowledge, or conversely, just how important it is for patent prosecution professionals to recognize and challenge unsupported assertions of common knowledge. Claim 1 is reproduced below:
1. A method for producing a raw comminuted meat product, the method including:
(a) receiving a stream of input material including pieces of meat;
(b) separating a first material and a second material from the stream of input material so that the first material and second material are separate from each other, the first material including liquified meat fat and being substantially free of lean meat and the second material including raw lean meat;
(c) forming meat fat granules from a portion of the first material; and
(d) combining a quantity of the meat fat granules at a meat fat blending temperature with a quantity of the second material at a lean meat blending temperature to produce a target comminuted meat product having a target lean point.
In this case, the examiner rejected the claims based on the assertion that the features disclosed in these references were “commonly included” in meat processing systems. However, the PTAB found that the examiner failed to provide adequate evidence to support the claim of common knowledge, leading to the reversal of the rejection. From the decision (internal citations omitted):
Examiner finds that Downing and Ciantar show features that meat processing systems commonly included. Those findings are not well taken because Examiner does not establish that the meat processing features disclosed by Downing or Ciantar were commonly included in meat processing systems. Examiner finds that “providing 100% fat first material and nearly 100% lean second material would have enabled greater control and flexibility over the fat content of the final meat product of Sullivan et al, since fat was commonly separated from meat products by liquefaction of the fat as shown by Ciantar et al and Downing”. Examiner does not point out where Downing or Ciantar support Examiner’s apparent finding that Downing and Ciantar would have suggested, to one of ordinary skill in the art, providing 100% fat first material and nearly 100% lean second material to enable greater control and flexibility over the fat content of a final meat product. Consequently, that finding appears to be based upon impermissible hindsight in view of Appellant’s disclosure.
Setting forth a prima facie case of obviousness requires establishing that one of ordinary skill in the art would have had an apparent reason to modify the prior art to arrive at the claimed invention. Examiner makes many fact findings that follow the word “since”. Examiner, however, never explains how the prior art would have provided one of ordinary skill in the art with an apparent reason to mix lean meat with liquified meat fat that is substantially free of lean meat to produce a comminuted meat product having a target lean point as required by Appellant’s independent claim
This case highlights the importance of backing up any claim of common knowledge with evidence. The references may have disclosed certain relevant features, but without proof that those features were indeed common knowledge in the art at the time of invention, the examiner’s rejection could not stand.
Patent prosecution professionals should recognize when an examiner is improperly relying on "common knowledge" to support an obviousness rejection and consider the following options for pushing back in practice:
Demand Evidence: when challenging an examiner’s assertion of common knowledge, require that they provide concrete evidence. Point to the MPEP guidelines and remind the examiner that such assertions must be substantiated with factual evidence.
Review Cited References Carefully: Ensure that the prior art references themselves do not merely hint at features but explicitly or implicitly disclose the features being relied upon a common in the field.
Leverage the MPEP: Use MPEP § 2144.03 to support arguments that examiner rejections based on common knowledge must be well-substantiated. Refer to the guidelines on what constitutes “objective evidence” of obviousness and remind the examiner of their burden of proof.
Consider your own evidence, including Expert Declarations: If necessary, consider submitting an expert declaration to counter any claims of common knowledge, particularly when there is a basis for the feature being uncommon.
While it may seem that an examiner’s use of “common” features is meant to make you feel that your claims are obvious, as shown in the example case above, such over-emphasis, when not supported, can be an opening for overcoming the rejection without any further amendments.