Even if a claim does not include the word “means,” there is only a rebuttable presumption, and not an absolute conclusion, that 35 U.S.C. § 112 ¶ 6 was not intended to govern the claim; a written description limitation should not be read into a claim if it is not used in the claim.

The patentee sued the alleged infringer for patent infringement. The alleged infringer then initiated an inter partes reexamination of the patent-in-suit in the United States Patent and Trademark Office (“PTO”).   

The reexamination resulted in the determination that certain claims were invalid under 35 U.S.C. §§ 102-103 because the examiner construed the disputed claim without the patentee’s argued for limitation. This determination was upheld by the Board of Patent Appeals and Interferences (“Board”) of the PTO. The Board’s decision was predicated on the interpretation of the disputed claim limitation in accordance with 35 U.S.C. § 112 ¶ 6. After reviewing the Board’s decision de novo, the Federal Circuit affirmed, but disagreed with the Board’s invocation of 35 U.S.C. § 112 ¶ 6 to reach its conclusion. 

The court held that the disputed claims do not require the patentee’s argued for limitation. Similarly, the Board reached the same conclusion but committed legal error in its analysis. That is, “[t]he Board determined that the presumption [that 35 U.S.C. § 112 ¶ 6 should not govern claim construction] was sufficiently rebutted because the disputed claim limitation [did] not recite sufficient structure for performing the recited function.” The Federal Circuit, however, explained that “failure to use the word ‘means’ creates a rebuttable presumption that the drafter did not intend the claims to be governed by § 112 ¶ 6” and that this presumption is not “easily rebutted.” Particularly in this case, where “the [disputed claim limitation] as used in the [patent-in-suit] and in common parlance, reasonably imparts sufficient structure so that the presumption against applying § 112, ¶ 6 in this context is not overcome.” In sum, the Federal Circuit held that the Board committed legal error in reaching its conclusion.

Nevertheless, the court agreed with the Board’s conclusion on different grounds. The limitation, which the patentee argued was in the claim, should not be read into the claims even though “the embodiments discussed in the patents have that limitation.” The court explained, “it is not proper to import from the patent’s written description limitations that are not found in the claims themselves.” Moreover, “because [the patentee] decided not to amend the disputed claims to directly include [the disputed limitation] when it had the opportunity to do so [during reexamination, the Federal Circuit], decline[d] to read such a limitation into the claims on appeal.”

A copy of the opinion can be found here