The Federal Circuit affirmed the decision of the Patent Trial and Appeal Board that challenged claims of Canon U.S.A. Inc. and Canon Inc.'s patent that discloses an improved fluid supply tank for a micro-fluid ejection head and method for improving operation of a micro-fluid ejection device are unpatentable, in an inter partes review by Slingshot Printing LLC. The court affirmed the board’s decision that the challenged claims are anticipated by and obvious over prior art.