Authorities Cited: United States Patent and Trademark Office U.S. Patent No. 6,216,235 Supreme Court 269 U.S. 459, 468 297 U.S. 496, 499 Circuit Courts 939 F.2d 1574 982 F.2d 1546, 1554 56 F.3d 1538, 1551 211 F.3d 1245, 1253 248 F.3d 1333 Federal Rules of Civil Procedure Fed. R. Civ. P. 19(a)