Alexander Milburn Co. v. Davis-Bournonville Co.
United States Supreme Court
270 U.S. 390 (1926)
Whitford's patent, issued in 1912, claimed an improvement that Clifford had already disclosed — but not claimed — in his own earlier-filed 1911 patent application, which issued before Whitford's. Alexander Milburn (defendant), sued for infringing the Whitford patent, argued Clifford was the true prior inventor of the claimed improvement, but the lower courts held that because Clifford never claimed the invention, he couldn't be considered a prior inventor for purposes of invalidating Whitford's patent.
Whether an inventor who claims an invention in a later-filed patent application can still obtain valid patent protection when an earlier-filed application disclosed, but did not claim, that same invention.