Appellant Regents of the University of Minnesota (“the University”) owns U.S. Patent No. 6,077,281 (“the ’281 patent”) and U.S. Patent No. 6,077,291 (“the ’291 patent”), which are directed to medical devices for repairing heart defects. The University accused AGA Medical Corporation (“AGA”) of infringing both patents. After claim construction, the district court granted summary judgment that the ’291 patent was not infringed and that the asserted claims of the ’281 patent were invalid as anticipated. The University appeals, arguing that the district court erred in its construction of the claims of the ’291 patent, and in finding the ’281 patent anticipated by a prior art device. We affirm.