Date:24 February 2023

【Volume 104】

We explored how Taiwan and China view whether an erroneous prior art disclosure may support obviousness in Part I and Part II of this 4-part series.

In this third segment, we look at the relevant regulations stipulated in the US Manual of Patent Examining Procedure and a recent US court judgment.

Part III. U.S.

U.S. judiciary has established the principle that “information with obvious error cannot be used as support of argument that the disputed claims have been disclosed” in the In re Yale case in 1970. Recently, the US Court of Appeals for the Federal Circuit (CAFC) further illustrated the concept of “obvious error” in LG Electronics Inc. v. ImmerVision, Inc. Similarly, the judgement in U.S. only mentions the result (1) in Part I of our series, i.e., to simply deny the legal validity of the erroneous part to be a disclosed prior art.

1. Manual of Patent Examining Procedure (MPEP)

   MPEP stipulates that when a prior art reference includes erroneous description, the erroneous information is without legal validity to be a disclosed prior art. The applicant bears the burden of proof to rebut the operability of the prior art. However, where a prior art appears not to be enabling on its face, the applicant has no burden of proof.

   MPEP § 2121 prescribes that:

   “2121 Prior Art…

   I. PRIOR ART IS PRESUMED TO BE OPERABLE/ENABLING

   When the reference relied on expressly anticipates or makes obvious all of the elements of the claimed invention, the reference is presumed to be operable. Once such a reference is found, the burden is on applicant to rebut the presumption of operability…See also MPEP § 716.07.

   Where a reference appears to not be enabling on its face, however, an applicant may successfully challenge the cited prior art for lack of enablement by argument without supporting evidence…

   See also MPEP § 716.07.”

   According to the regulations of the MPEP above, MPEP § 716.07 is cited in § 2121 to further provide the following example for arguments against the operability of prior arts:

   “716.07 Inoperability of References...

   ... In re Yale, 434 F.2d 66, 168 USPQ 46 (CCPA 1970) (Correspondence from a co-author of a literature article confirming that the article misidentified a compound through a typographical error that would have been obvious to one of ordinary skill in the art was persuasive evidence that the erroneously typed compound was not put in the possession of the public.).”

   By citing the In re Yale case, MPEP provides an example for arguments challenging the prior art with erroneous description. Namely, where an error existing in the prior art reference is proved to be obvious to a person skilled in the art (e.g., typographical error in the In re Yale case), such erroneous information does not provide a valid disclosure.

2. Court Judgment

   (1) In re Yale, 434 F.2d 666 (C.C.P.A. 1970)¹

   The following criterion was established in the In re Yale case for errors in prior art documents (hereafter Yale standard):

   “where a prior art reference includes an obvious error of a typographical or similar nature that would be apparent to one of ordinary skill in the art who would mentally disregard the errant information as a misprint or mentally substitute it for the correct information, the errant information cannot be said to disclose subject matter… The remainder of the reference would remain pertinent prior art disclosure.”

   (2) LG Electronics Inc. v. ImmerVision, Inc., Case Nos. 21-2037; -2038, Fed. Cir. Jul. 11, 2022²

   Recently, the Yale standard was cited again by CAFC in the judgement of LG Electronics Inc. v. ImmerVision, Inc.

   Case facts

   The plaintiff, LG Electronics Inc (hereinafter LG), filed a pair of petitions for inter partes review (IPR), each challenging one of the claims of U.S. Patent No. 6,844,990 (hereinafter ‘990 patent) held by defendant ImmerVision, Inc. (hereinafter ImmerVision). Fundamental to LG’s obviousness arguments is that the relevant technical features of the ‘990 patent have been disclosed by U.S. Patent No. 5,861,999 (“Tada”).

   However, through experiments, ImmerVision’s expertwitness found that one of Tada’s Embodiments on which LG relied as prior art disclosure described incorrect values, thereby finding that such erroneous description is a copy-and-paste error from Tada’s another incompatible Embodiment, and thus the values were inconsistent with the correct ones in Japanese Priority Application. In the case the values are corrected, said Embodiment does not disclose relevant technical features.

   Patent Trial and Appeal Board (PTAB) heard the above IPR petitions. In the decision of IPR2020-00179 and IPR2020-00195, the Board found that said erroneous description in Tada was an apparent error that would have been disregarded or corrected by a person of ordinary skill in the art in. Thus, relying on Yale standard, the Board deemed Tada did not disclose relevant technical features of the ‘990 patent.

   Main Issues of the Case

   LG was dissatisfied with the Board’s decisions and thus appealed to CAFC, arguing that the erroneous description in Tada was not an obvious error mainly for the following reasons:

   (i) LG argued that Yale standard requires a person of ordinary skill in the art to “immediately recognize” the apparent error as incorrect. However, a “convoluted process” through complex analysis and resort to extrinsic information was required for ImmerVision’s expert to take “10 to 12 hours” to discover the error in Tada, and such error has not been discovered in the public domain for over 20 years.

   (ii) LG argued that Yale standard should be narrowly limited to spelling mistakes, while the error in Tada was beyond a typographical error.

   CAFC Opinion

   The CAFC affirmed PTAB’s opinion, and thus rejected LG’s abovementioned arguments. The CAFC considered that the length of time and the particular manner in which the error was actually discovered did not diminish that there was an obvious error in Tada within the meaning of Yale. Contrary to LG’s assertions, Yale does not impose a temporal requirement. In addition, CAFC concluded that there was no meaningful difference between the obvious “typographical” error in Yale and the copy-and-paste error in Tada.

3. Conclusion

   U.S. judiciary has established the principle that “information with obvious error cannot be used as support of argument that the disputed claims have been disclosed” in the In re Yale case in 1970. The Yale standard appears to adopt a strict requirement, limited only to the circumstances where “an obvious error of a typographical or similar nature exists” and “such an error shall be apparent to one of ordinary skill in the art who would mentally disregard the errant information as a misprint or mentally substitute it for the correct information”, that the errant information cannot be available as prior art. However, in a recent case LG Electronics Inc. v. ImmerVision, Inc., CAFC considered that the determination of whether a prior art reference includes an “obvious error” is not based on the amount of time and efforts or complexity of the process to detect the error.

   In both LG Electronics Inc. v. ImmerVision, Inc. and the In re Yale case, the discovery of the error is based on the prior art document “itself”, i.e. the error that could be detected by inspection within the scope of the prior art document itself. In other words, the so-called “obvious” in these cases focuses more on the internal consistency within a prior art reference, rather than the common sense meaning of “immediately recognizable”.

   On the other hand, the judgement in LG Electronics Inc. v. ImmerVision, Inc., relying on the Yale standard, only denies the legal validity of the erroneous part to be an available prior art, i.e., simply mentions the result (1) in Part I of our series. In comparison, the European Patent Office further inspects whether the corrected content may be eligible as prior art disclosure, which will be introduced in detail in the last part of this series.