Prosthetic Sock Claims Invalid In Light Of Prosthetic Socks

Posted on | January 18, 2010 | 1 Comment

2010-1119 Ohio Willow v. Thermo-Ply
ED/TX 07-cv-274
Judge Ron Clark

Patentee American Willow appeals from the summary judgment order of Judge Ron Clark finding the asserted claims of 7,291,182 invalid under §§ 102 and 103.  The '182 patent generally is directed at a coated fabric liner for prosthetics. 

The case also involved an intervenor seeking to be added as an inventor (denied), and Thermo-Ply's motion to add Walker Process counterclaims based on fraud before the PTO (denied).  The case was recently covered by Michael Smith over at EDTexweblog.

Judge Clark ultimately finds nearly 50 claims from the '182 invalid as obvious in light of a prior art product called the "Silosheath" (which, as is clear from the name, is a tube-sock shaped cloth that fits over an amputee's silo a/k/a stump or, as the court occasionally refers to it, the residuum), U.S. 4,923,474 ("the Klasson patent), and the common sense and knowledge of one of ordinary skill in the art.

A representative claim from the '182 patent is claim 1:

A cushion liner for enclosing an amputation stump, said liner comprising a fabric covering having an open end for introduction of said stump and a closed end opposite said open end, said fabric coated seamlessly on only an inside surface thereof with a polymeric cushioning gel that substantially conforms to the shape of said amputation stump when said liner is worn; wherein said liner is configured such that said polymeric cushioning gel is in contact with the skin of said amputation stump when said liner is worn by a user thereof.

The rest of the claims specified details relating to the fabric, gel, etc.

Essentially, the court found that using a liner with gel cushioning was well known in the art, and all the details claimed by the '182 patent were already known or were obvious to try. 

As a threshold issue, he rejects Ohio Willow's initial effort to distinguish the Silosheath because it is a "sheath" while the '182 claims a "cushion liner."  After noting that the Silosheath was cited to the PTO during prosecution and admitted as prior art, the court concluded:

[M]erely assigning a new name to an invention does not distinguish it from the prior art.

Order, p. 6.  Once the Silosheath is considered, Judge Clark's analysis is relatively straight forward. 

After running though the claims, the court also dispenses with the secondary considerations.  While acknowledging the commercial success that the embodiment of the '182 patent has enjoyed, the court downplays that factor and references the recent Ritchie decision from the Federal Circuit:

“[t]he commercial success of a product can have many causes unrelated to patentable inventiveness; for example, the commercial success of an “invention” might be due not to the invention itself but to skillful marketing of the product embodying the invention.” Ritchie v. Vast Resources, Inc., 563 F.3d 1334, 1336 (Fed. Cir. 2009).  Commercial success is insufficient to overcome the obviousness challenge when the inventions are “modest, routine, everyday, incremental improvements of an existing product or process that confer commercial value (otherwise they would not be undertaken) but do not involve sufficient inventiveness to merit patent protection.” Id. at 1337. 

Order, p. 18.  The court concluded:

“a strong prima facie obviousness showing may stand even in the face of considerable evidence of secondary considerations.” Rothman v. Target Corp., 556 F.3d 1310, 1322 (Fed. Cir. 2009); see also Leapfrog Enters., Inc. v. Fisher-Price, Inc., 485 F.3d 1157, 1162 (Fed. Cir. 2007).

Order, p. 19.

2010-1119 SJ Order

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