The United States Patent and Trademark Office (USPTO) issued an update to its obviousness guidelines to be used when applying the law of obviousness under 35 U.S.C. 103. This 2010 KSR Guidelines Update highlights case law developments on obviousness under 35 U.S.C. 103 since the 2007 decision by the United States Supreme Court (Supreme Court) in KSR Int’l Co. v. Teleflex Inc. These guidelines are intended to be used by Office personnel in conjunction with the guidance in the Manual of Patent Examining Procedure when applying the law of obviousness under 35 U.S.C. 103.


The purpose of the 2010 KSR Guidelines Update is to remind Office personnel of the principles of obviousness explained by the Supreme Court in KSR Int’l Co. v. Teleflex Inc., 550 U.S 398 (2007) (KSR), and to provide additional guidance in view of decisions by the United States Court of Appeals for the Federal Circuit (Federal Circuit) since KSR.

Principles of Obviousness and the Guidelines.

In response to the Supreme Court’s April 2007 decision in KSR, the Office developed guidelines for patent examiners to follow when determining obviousness of a claimed invention and published these guidelines in the Federal Register and Official Gazette. See Examination Guidelines for Determining Obviousness Under 35 U.S.C. 103 in View of the Supreme Court Decision in KSR International Co. v. Teleflex Inc., 72 FR 57526 (Oct. 10, 2007), 1324 Off. Gaz. Pat. Office 23 (Nov. 6, 2007) (2007 KSR Guidelines). The 2007 KSR Guidelines have been incorporated in the MPEP. See MPEP § 2141 (8th ed. 2001) (Rev. 6, Sept. 2007). The purpose of the 2007 KSR Guidelines was to give Office personnel practical guidance on how to evaluate obviousness issues under 35 U.S.C. 103(a) in accordance with the Supreme Court’s instruction in KSR. The 2007 KSR Guidelines also alerted Office personnel to the importance of considering rebuttal evidence submitted by patent applicants in response to obviousness rejections.

The 2007 KSR Guidelines pointed out, as had the Supreme Court in KSR, that the factual inquiries announced in Graham v. John Deere, 383 U.S. 1, 17-18 (1966) (scope and content of the prior art; differences between the claimed invention and the prior art; level of ordinary skill in the art; and secondary indicia of nonobviousness), remain the foundation of any determination of obviousness. It remains true that “[t]he determination of obviousness is dependent on the facts of each case.”Sanofi-Synthelabo v. Apotex, Inc., 550 F.3d 1075, 1089 (Fed. Cir. 2008) (citing Graham, 383 U.S. at 17-18 (1966)). As for the reasoning required to support an obviousness determination, the 2007 KSR Guidelines noted that the teaching-suggestion-motivation (TSM) test was but one possible approach. The 2007 KSR Guidelines identified six other rationales gleaned from the KSR decision as examples of appropriate lines of reasoning that could also be used.

The six other rationales identified in the 2007 KSR Guidelines are: (1) Combining prior art elements according to known methods to yield predictable results; (2) simple substitution of one known element for another to obtain predictable results; (3) use of a known technique to improve similar devices, methods, or products in the same way; (4) applying a known technique to a known device, method, or product ready for improvement to yield predictable results; (5) obvious to try—choosing from a finite number of identified, predictable solutions, with a reasonable expectation of success; and (6) known work in one field of endeavor may prompt variations of it for use in either the same field or a different one based on design incentives or other market forces if the variations are predictable to one of ordinary skill in the art. Any rationale employed must provide a link between the factual findings and the legal conclusion of obviousness.

The Impact of the KSR Decision.

KSR’ s renewed emphasis on the foundational principles of Graham coupled with its abrogation of the strict TSM test have clearly impacted the manner in which Office personnel and practitioners carry out the business of prosecuting patent applications with regard to issues of obviousness. However, Office personnel as well as practitioners should also recognize the significant extent to which the obviousness inquiry has remained constant in the aftermath of KSR.

In footnote 2 of the 2007 KSR Guidelines, the Office acknowledged that ongoing developments in the law of obviousness were to be expected in the wake of the KSR decision. That footnote also stated that it was “not clear which Federal Circuit decisions will retain their viability” after KSR. See 2007 KSR Guidelines, 72 FR at 57,528 n.2. The edition of the MPEP that was current when the KSR decision was handed down had made the following statement in § 2144:

The rationale to modify or combine the prior art does not have to be expressly stated in the prior art; the rationale may be expressly or impliedly contained in the prior art or it may be reasoned from knowledge generally available to one of ordinary skill in the art, established scientific principles, or legal precedent established by prior case law.MPEP § 2144 (8th ed. 2001) (Rev. 5, Aug. 2006) (citing five pre-KSR Federal Circuit opinions and two decisions of the Board).

The KSR decision has reinforced those earlier decisions that validated a more flexible approach to providing reasons for obviousness. However, the Supreme Court’s pronouncement in KSR has at the same time clearly undermined the continued viability of cases such as In re Lee, 277 F.3d 1338 (Fed. Cir. 2002), insofar as Lee appears to require a strict basis in record evidence as a reason to modify the prior art.

The Supreme Court’s flexible approach to the obviousness inquiry is reflected in numerous pre-KSR decisions, as can be seen in a review of MPEP § 2144. This section provides many lines of reasoning to support a determination of obviousness based upon earlier legal precedent that had condoned the use of particular examples of what may be considered common sense or ordinary routine practice (e.g., making integral, changes in shape, making adjustable). Thus, the type of reasoning sanctioned by the opinion in KSR has long been a part of the patent examination process. See MPEP § 2144.

Although the KSR approach is flexible with regard to the line of reasoning to be applied, the 2007 KSR Guidelines and MPEP § 2143 state: “The Supreme Court in KSR noted that the analysis supporting a rejection under 35 U.S.C. 103 should be made explicit.” MPEP § 2143. In Ball Aerosol v. Limited Brands, 555 F.3d 984 (Fed. Cir. 2009), the Federal Circuit offered additional instruction as to the need for an explicit analysis. The Federal Circuit explained, as is consistent with the 2007 KSR Guidelines, that the Supreme Court’s requirement for an explicit analysis does not require record evidence of an explicit teaching of a motivation to combine in the prior art.

[T]he analysis that “should be made explicit” refers not to the teachings in the prior art of a motivation to combine, but to the court’s analysis * * *. Under the flexible inquiry set forth by the Supreme Court, the district court therefore erred by failing to take account of “the inferences and creative steps,” or even routine steps, that an inventor would employ and by failing to find a motivation to combine related pieces from the prior art.” Ball Aerosol, 555 F.3d at 993.

The Federal Circuit’s directive in Ball Aerosol was addressed to a lower court, but it applies to Office personnel as well. When setting forth a rejection, Office personnel are to continue to make appropriate findings of fact as explained in MPEP §§ 2141 and 2143, and must provide a reasoned explanation as to why the invention as claimed would have been obvious to a person of ordinary skill in the art at the time of the invention. This requirement for explanation remains even in situations in which Office personnel may properly rely on intangible realities such as common sense and ordinary ingenuity.

When considering obviousness, Office personnel are cautioned against treating any line of reasoning as a per se rule. MPEP § 2144 discusses supporting a rejection under 35 U.S.C. 103 by reliance on scientific theory and legal precedent. In keeping with the flexible approach and the requirement for explanation, Office personnel may invoke legal precedent as a source of supporting rationale when warranted and appropriately supported. See MPEP § 2144.04. So, for example, automating a manual activity, making portable, making separable, reversal or duplication of parts, or purifying an old product may form the basis of a rejection. However, such rationales should not be treated as per se rules, but rather must be explained and shown to apply to the facts at hand. A similar caveat applies to any obviousness analysis. Simply stating the principle (e.g.,“art recognized equivalent,” “structural similarity”) without providing an explanation of its applicability to the facts of the case at hand is generally not sufficient to establish a prima facie case of obviousness.

Many basic approaches that a practitioner may use to demonstrate nonobviousness also continue to apply in the post-KSR era. Since it is now clear that a strict TSM approach is not the only way to establish a prima facie case of obviousness, it is true that practitioners have been required to shift the emphasis of their nonobviousness arguments to a certain degree. However, familiar lines of argument still apply, including teaching away from the claimed invention by the prior art, lack of a reasonable expectation of success, and unexpected results. Indeed, they may have even taken on added importance in view of the recognition in KSR of a variety of possible rationales.

At the time the KSR decision was handed down, some observers questioned whether the principles discussed were intended by the Supreme Court to apply to all fields of inventive endeavor. Arguments were made that because the technology at issue in KSR involved the relatively well-developed and predictable field of vehicle pedal assemblies, the decision was relevant only to such fields. The Federal Circuit has soundly repudiated such a notion, stating that KSR applies across technologies:

This court also declines to cabin KSR to the “predictable arts” (as opposed to the “unpredictable art” of biotechnology). In fact, this record shows that one of skill in this advanced art would find these claimed “results” profoundly “predictable.” In re Kubin, 561 F.3d 1351, 1360 (Fed. Cir. 2009).

Thus, Office personnel should not withdraw any rejection solely on the basis that the invention lies in a technological area ordinarily considered to be unpredictable.

The decisions of the Federal Circuit discussed in this 2010 KSR Guidelines Update provide Office personnel as well as practitioners with additional examples of the law of obviousness. The purpose of the 2007 KSR Guidelines was, as stated above, to help Office personnel to determine when a claimed invention is not obvious, and to provide an appropriate supporting rationale when an obviousness rejection is appropriate. Now that a body of case law is available to guide Office personnel and practitioners as to the boundaries between obviousness and nonobviousness, it is possible in this 2010 KSR Guidelines Update to contrast situations in which the subject matter was found to have been obvious with those in which it was determined not to have been obvious. Thus, Office personnel may use this 2010 KSR Guidelines Update in conjunction with the 2007 KSR Guidelines (incorporated into MPEP §§ 2141 and 2143) to provide a more complete view of the state of the law of obviousness.

See all of the 2010 KSR Guidelines Update here.

Members of the public are invited to provide comments on the 2010 KSR Guidelines Update. The Office is especially interested in receiving suggestions of recent decisional law in the field of obviousness that would have particular value as teaching tools.

Comments concerning the KSR Guidelines Update may be sent by electronic mail message over the Internet addressed to, or submitted by mail addressed to: Mail Stop Comments—Patents, Commissioner for Patents, P.O. Box 1450, Alexandria, VA 22313-1450. Although comments may be submitted by mail, the Office prefers to receive comments via the Internet.

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  1. […] decisions of the Federal Circuit discussed in the 2010 KSR Guidelines Update provide additional examples of the law of obviousness. The purpose of the 2007 KSR Guidelines was […]

  2. This is about KSR. I have shown that KSR had not had any negative effect on patent prosecution. If anything, KSR has increased the popularity of the TSM-test, and has validated the TSM-test. (I would be interested in any file histories that show a negative effect of KSR on prosecution.) I read 300 post-KSR file histories, and published the results of my analysis. To repeat, according to my reading of 300-file history, KSR has not had the predicted negative effect. See, Brody, T. (2010) Obviousness in patents following the U.S. Supreme Court’s decision of KSR International Co. v. Teleflex, Inc. in Journal Patent Trademark Office Society 92:26-70.

  3. […] Examination guidelines update: developments in the obviousness inquiry after KSR v.Teleflex (Patent Docs) […]

  4. i still think that the obvious to try rationale is problematic in that it subtly encourages the use of hindsight bias.

    the ‘common sense’ rationale is simply absurdity….