Generic description of function and location fails to recite definite structure for means-plus-function limitation
The parties disputed whether “cheque standby unit” in an ATM machine was a means-plus-function limitation, which was required to comply with the requirements of §112, paragraph 6. Relying on the testimony of the patentee’s expert, the ITC concluded that the term “cheque standby unit” itself conveyed a structure to a person of skill in the art, and thus was not a means-plus-function limitation subject to the requirements of § 112, paragraph 6. Based on this construction, the ITC found the claims valid and infringed. The Federal Circuit disagreed and found that the “cheque standby unit” was a means-plus-function limitation and failed to disclose a structure sufficient to meet the requirements of § 112, paragraph 6.
In reversing the ITC, the Federal Circuit first addressed whether the “cheque standby unit” was a means-plus-function term. Although recognizing the rebuttable presumption that claim terms that do not include the word “means” are not means-plus-function limitations, the court found that the presumption had been overcome by the patent’s intrinsic evidence. The specification and claims only described the “cheque standby unit” in terms of its function and location in the apparatus. In reaching its conclusion the court rejected the patentee’s argument that expert testimony is required to evaluate whether a term sufficiently connotes structure to a person of ordinary skill in the art. Rather, the court found that such expert testimony was extrinsic evidence that was insufficient to overcome the intrinsic record here. Having determined that the “cheque standby unit” was a means-plus-function, the court considered whether the specification disclosed the necessary structure to comply with §112, paragraph 6 and found no such structure. Accordingly, the “cheque standby unit” was indefinite.