This appeal concerns the lawful rate for transportation of natural gas by United Gas Pipe Line Company for Southern Natural Gas Company during the period May 1, 1963, through May 25, 1965. Petitioner contends that the rate filed, charged and collected by United was unilaterally imposed and is therefore void under United Gas Pipe Line Co. v. Mobile Gas Service Corp., 350 U.S. 332, 76 S.Ct. 373, 100 L.Ed. 373 (1956), and Tyler Gas Service Company v. Federal Power Comm., 101 U.S.App.D.C. 184, 247 F.2d 590, cert. denied, sub nom. United Gas Pipe Line Co. v. Tyler Gas Service Co., 355 U.S. 895, 78 S.Ct. 263, 2 L.Ed.2d 193 (1957). We agree with the Commission that the rate, however imposed initially, was thereafter bilaterally agreed upon and, consequently, was not void under the principles announced in the Mobile and Tyler cases.

Affirmed.