“Outer surface” cannot encompass interior surface based on statements made in prosecution historySeptember 7, 2007

The Federal Circuit yesterday reversed a district court's claim construction and its corresponding determination of literal infringement. The court found that the prosecution history of the patents negated the district court's claim construction, and that, properly construed, there could be no literal infringement.The term at issue was the "outer surface" of a drive collar. The district court held that that "outer surface" of the claimed drive collar could be construed to include "a collar whose interior, not exterior, accepts the drive tool." The Federal Circuit disagreed, finding statements made during prosecution to distinguish a prior art reference to preclude a construction that included collars whose interiors accept the drive tool.More details of Gillespie v. Dywidag Sys. Int'l after the jump. At issue was a mine roof bolt manufactured by the defendant, Dywidag Systems. Dywidag conceded its device to meet all the claim limitations of Gillespie patents 5,230,589 and 5,259,703 except for a drive collar limitation. The Gillespie mine roof bolt is made of steel cable with various structural components that help reinforce and support the rock formation above a mine roof. The Gillespie bolt uses a drive collar surrounding a tapered plug to rotate the bolt:The accused Dywidag mine roof bolt, on the other hand, uses a key socket recessed in the end of the bolt head: The disputed drive collar limitation is found in claim clause (c) of both claim 1 of the '589 patent and claim 15 of the '703 patent.

1. A mine roof bolt comprising: (a) a length of multi-strand cable defining a bolt shank; (b) a tapered plug comprising a body portion having an internal bore and a frusto-conical outer surface essentially concentric with said internal bore, said tapered plug being mounted about an end of said cable at said internal bore; and (c) an internally tapered drive collar having a frusto-conical inner surface that engages said frusto-conical outer surface of said tapered plug, and having an outer surface defining a drive head that accepts a driving mechanism for rotating and linearly translating said bolt, wherein said tapered plug is mounted on an end of said cable, and said drive collar is pressed down upon said tapered plug, forcing said tapered plug against said cable, such that said drive collar, said tapered plug, and said cable, when fitted tightly together, define said mine roof bolt.

Claim 15 of the '703 patent, a continuation of the '589 patent, is as follows:

5. A mine roof bolt comprising: (a) a length of multi-strand cable defining a bolt shank; (b) a tapered plug comprising a body portion having an internal bore and a frusto-conical outer surface essentially concentric with said internal bore, said tapered plug being mounted about an end of said cable at said internal bore; (c) an internally tapered drive collar having a frusto-conical inner surface that engages said frusto-conical outer surface of said tapered plug, and having an outer surface defining a drive head that accepts a driving mechanism for rotating and linearly translating said bolt, wherein said tapered plug is mounted on an end of said cable, and said drive collar is pressed down upon said tapered plug, forcing said tapered plug against said cable, such that said drive collar, said tapered plug, and said cable, when fitted tightly together, define said mine roof bolt; and (d) a stiffner sleeve mounted on said cable adjacent said drive collar for minimizing buckling of said cable as said mine roof bolt is being inserted into a bore hole, and for protecting said cable from damage from a mine roof bolt plate as said mine roof bolt is being rotated into a bore hole.

Dywidag argued that because its device "is rotated by way of a key socket recessed in the end of the bolt head" there could be no literal infringement of the Gillespie device that is rotated by a "drive collar . . . having an outer surface defining a drive head that accepts a drive mechanism." Thus, Dywidag's argument centered on the plain meaning of the term "outer" to mean the exterior of the drive head. Dywidag also pointed to the prosecution history of the patents, asserting that a broader construction was precluded by arguments made to distinguish the prior art.The district court, in siding with Gillespie, found that the "outer surface" of the Gillespie bolt was not in reference to the exterior surface of the drive head, but rather is "relative to the frusto-conical 'inner' surface portion thereof." The district court found that although the plain meaning of term "outer" means "exterior," the court must also establish "the ordinary meaning that would be attributed to those words by persons skilled in the relevant art."In reversing the district court, the Federal Circuit paid close attention to the prosecution history of the Gillespie patents. The court found that "Mr. Gillespie clearly used 'outer' to refer to the outside surface of the bolt head" when attempting to distinguish his invention over the prior art. Moreover, the prior art, according to Mr. Gillespie, had a "cylindrical outside surface . . . incapable of being driven by a mine roof bolting machine." The court reiterated that a "patentee is held to what he declares during the prosecution of his patent." As a result, the court concluded that any construction encompassing "a collar whose interior, not exterior, accepts the drive tool" was precluded by the prosecution history of the patent.As a result, the court reversed the district court's claim construction, and held under the proper construction there was no infringement.To read the full decision in Gillespie v. Dywidag Sys. Int'l, click here.