Opinion ID: 210398
Heading Depth: 2
Heading Rank: 3

Heading: Broadening Reissue

Text: Ivax and Cipla argue that claim 11 of the '712 patent is invalid because it represents a broadening of original claim 11. They argue that the change in the optical rotation sign of the diol intermediate in claim 11 during reissue was clearly a broadening of the claim because the claim now covers a process beginning with a different enantiomer. Ivax and Cipla also argue that a typographical error may nonetheless be broadening and that a typographical error must be evident to the general public in order to serve the public notice function of patents. In response, Forest argues that the district court correctly determined that the reissue application corrected a typographical error that was readily apparent to one of ordinary skill in the art reviewing the patent and therefore did not result in any change in the scope of the patent. The reissue statute reads as follows: Whenever any patent is, through error without any deceptive intention, deemed wholly or partly inoperative or invalid, by reason of . . . the patentee claiming more or less than he had a right to claim in the patent, the Director shall . . . reissue the patent for the invention disclosed in the original patent . . . for the unexpired part of the term of the original patent. . . . No reissued patent shall be granted enlarging the scope of the claims of the original patent unless applied for within two years from the grant of the original patent. 35 U.S.C. § 251. The '712 reissue patent resulted from an application filed more than two years after the grant of the original patent, and the claims of a reissue patent filed after that date are invalid if they enlarge the scope of the original claims. See 35 U.S.C. § 282; Quantum Corp. v. Rodime PLC, 65 F.3d 1577, 1583 (Fed.Cir.1995). However, a change in a reissue application that is only clerical does not necessarily broaden the scope of the claims and so does not render the patent invalid. The question before us is whether the change effected in the reissue application here broadened the scope of claim 11 or merely clarified or corrected the original claim. Comparison of the scope of the reissue claims with the claims of the original patent is a matter of claim construction, and it is performed from the perspective of one having ordinary skill in the art. See Pannu v. Storz Instruments, Inc., 258 F.3d 1366, 1370 (Fed.Cir.2001); Phillips v. AWH Corp., 415 F.3d 1303, 1313 (Fed.Cir. 2005) (en banc). Whether the claims of a reissue patent violate 35 U.S.C. § 251 is a question of law that we review de novo based on underlying facts reviewed for clear error. Medtronic, Inc. v. Guidant Corp., 465 F.3d 1360, 1373 (Fed.Cir.2006). We agree with Forest that the change in the optical rotation sign for the diol intermediate in claim 11 of the '712 patent did not broaden the scope of the claim. The patent specification supports, even compels, this conclusion. In Reaction Scheme I, the process begins with a racemic mixture of the diol intermediate. See '712 patent col.5 ll.41-42. The diagram of Reaction Scheme I reinforces that conclusion because it includes a notation next to the diagram of the diol intermediate that reads (+) and (-). '712 patent (emphasis added). The patent then describes a reaction sequence that results in production of the ester as a diastereomeric mixture. Id. at col.5 ll.47-48. It is the diastereomeric mixture of an ester (of a monoalcohol) that is then subjected to HPLC to produce an enantiomerically pure compound that can be converted into the desired (+)-citalopram end product. Id. at col.5 ll.47-59. Further, as found by the district court, because Reaction Scheme I begins with the racemate of the diol intermediate, the patent is ambiguous as to which enantiomer of the diol intermediate is actually converted to (+)-citalopram. In contrast, while the description of Reaction Scheme II also begins with the racemate of the diol intermediate, it is the diol intermediate itself that is resolved to produce an enantiomerically pure product compound. Id. at col.6 ll.8-33. The description also specifically describes using the (-)-diol intermediate to produce (+)citalopram. Id. at col.6 ll.29-42. Further support is again provided by the diagram of Reaction Scheme II, which includes a notation that reads (-) or (+) next to the structural diagram of citalopram. '712 patent (emphasis added). Thus, the enantiomeric labeling for the end product is reversed from that of the starting compound. Given this plain reading and the additional supporting expert testimony also relied upon by the district court, we see no error in the district court's finding that a person of ordinary skill in the art reviewing the patent would find the error in claim 11 relating to the optical sign of the diol intermediately apparent. The diagram of Reaction Scheme II makes clear that it is the (-)-diol that is converted to (+)-citalopram and that the correction in the claim corresponds to the disclosure in the specification. We therefore agree that the change in the optical sign during reissue does not represent a change of claim scope, but merely a correction of the claim to be consistent with the disclosure of the specification.