Either the rights or the document
Arneson 10, J.D. Candidate 2011, University of Minnesota Law School; B.A. 2001, St. Olaf College; Ph.D., 2007, Mayo Graduate School. (Laura N., December, 2010, “Article: Defining Unpatented Article: Why Labeling Products with Expired Patent Numbers Should Not Be False Marking”, 95 Minn. L. Rev. 650, 667. Lexis accessed online via KU libraries)
The Solo Cup court also held that an article covered by an expired patent should be considered an unpatentable article as a matter of statutory interpretation. 109 The statute, the Federal Circuit concluded, was "unambiguous." 110 Curiously, the Federal Circuit did not explain why it considered the statutory language unambiguous. The term "patent" may refer to either the "governmental grant" of the patent rights or to the "official document" that describes the invention. 111 [[Footnote 111 begins]] Black's Law Dictionary 1156 (8th ed. 2004); see also, e.g., Kemin Foods, L.C. v. Pigmentos Vegetales del Centro S.A. de C.V., 301 F. Supp. 2d 970, 974 (S.D. Iowa 2004) ("A patent is a legal document that defines the metes and bounds of the patentee's invention."). [[Footnote 111 ends]] Although the governmental grant of rights has clearly ended after the patent has expired, the document describing the invention and granting the rights continues to exist. Thus, an article described in an expired patent, and marked with the number of an expired patent document, may be viewed as covered by a patent rather than "unpatented."