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If there’s a typo

In prior art reference

Is it obvious?

'Clouds over the port' by heiwa4126 is licensed under CC BY 2.0.The Federal Circuit has held that a transcription error in a prior art document wouldn’t have been relied on by a person of ordinary skill in the art (POSITA) and thus couldn’t be used to prove obviousness.

The court noted that

This appeal requires us to consider how to treat a prior art reference in which the alleged teaching of a claim element would be understood by a skilled artisan not to be actual teaching, but rather to be an obvious error of a typographical or similar nature.

LG Electronics Inc. appealed from the United States Patent Trial and Appeal Board’s decisions in inter partes review proceedings challenging claims of an ImmerVision patent for “capturing and displaying digital panoramic images.”

LG’s obviousness arguments were based on the prior existence of U.S. Patent No. 5,861,999 (“Tada”), directed to a “Super Wide Angle Lens System Using an Aspherical Lens.”

As the court explained,

Panoramic (e.g., super-wide angle) objective lenses typically have linear image point distribution functions. This means there is a linear relationship between the distance of an image point from the image’s center and the corresponding relative angle of the object point to the image’s center. While this linearity allows digital panoramic images to be easily rotated, shifted, and enlarged or shrunk, it also limits image quality to “the resolution of the image sensor used when taking the initial image.” … This limitation on image quality is most noticeable when enlarging sectors of the image. The ’990 patent purports to improve the resolution of particular sectors of a digital panoramic image “without the need to increase the number of pixels per unit of area of an image sensor or to provide an overlooking optical enlargement system.”

Experts hired by both parties tried to make the lens described in the patent. ImmerVision’s expert, David Aikens, replicated the model used by LG’s expert but discovered the image was distorted.

He eventually figured out what the problem was. As the court explained:

It became clear to Mr. Aikens that, after ‘chang[ing] the aspheric coefficients [of his model] to match’ those of the Japanese Priority Application, the aspheric coefficients in the Japanese Priority Application were the correct ones and that they yielded a lens surface that was ‘a perfect match to the surface described in Table 6.’ J.A. 3042 (Aikens Decl. ¶¶ 74–75). In other words, there was a transcription, or copy-and-paste, error in Tada. The disclosures in Tada’s Table 5, which were intended to correspond to its Embodiment 3, were actually identical to those in Table 3, which corresponded to Embodiment 2

In both proceedings, the Board found that since “the correct aspheric coefficients in Table 5 of the Japanese Priority Application do not satisfy the language of the challenged claims,” LG had not proven the patent claims unpatentable as obvious.

As the court stated,

the Board found that the “disclosure of aspheric[] coefficients in Table 5 of Tada is an obvious error” that a person of ordinary skill in the art would have recognized and corrected.

The court cited a prior case in which it was held:

[W]here 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 the subject matter.

Judge Pauline Newman dissented in part because she didn’t agree that the error was “typographical or similar in nature”:

An ‘obvious error’ should be apparent on its face and should not require the conduct of experiments or a search for possibly conflicting information to determine whether an error exists….

The error in the Tada reference is plainly not a ‘typographical or similar error,’ for the error is not apparent on its face, and the correct information is not readily evident. It should not be necessary to search for a foreign document in a foreign language to determine whether there is an inconsistency in a United States patent.


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