This is an appeal from a dismissal by the District Court of appellants’ complaint under 35 U.S.C. § 145 (1958) which sought to compel the Patent Office to declare an interference between appellants’ application and a patent granted to one Heritage. The subject matter is the manufacture of composition board which utilizes the bark of coniferous trees as an essential ingredient, and more particularly the cork component of the bark.

Appellee contends, and the District Court agreed, that appellants’ application did not disclose substantially the same patentable invention as that of Heritage for the reason that the Heritage patent contemplated the complete isolation of the cork component from the rest of the bark, treatment of the cork, and a mixing of the pure cork back into the wood fibers as a separate step in the process, whereas appellants’ application did not. Upon review of the entire record we think that the District Court applied the correct standard in evaluating the evidence before it, and that its findings are supported by the evidence.

Affirmed.