Molybdenum Corp. of America v. Kasey, 279 F.2d 216 (9th Cir. 1960) (per curiam); 16 Charles A. Wright, Arthur R. Miller, Edward H. Cooper Eugene Gressman, Federal Practice and Procedure § 3929, at p. 142 (1977). But it would not require us to do so, as would a development that made the district judge's ruling of which an immediate appeal was sought moot. Moreau v. Tonry, 554 F.2d 163 (5th Cir. 1977) (per curiam); see also New York City Health Hospitals Corp. v. Blum, 678 F.2d 392, 397 (2d Cir. 1982); Oneida Indian Nation v. County of Oneida, 622 F.2d 624, 628-29 (2d Cir. 1980). Jurisdiction ordinarily is determined by the facts that exist when the case is filed, Newman-Green, Inc. v. Alfonzo-Larrain, 490 U.S. 826, 830, 109 S.Ct. 2218, 2222, 104 L.Ed.2d 893 (1989); Smith v. Sperling, 354 U.S. 91, 93 n. 1, 77 S.Ct. 1112, 1113, n. 1, 1 L.Ed.2d 1205 (1957); appellate jurisdiction, therefore, by the facts that exist when the appeal is filed.

When the Court of Appeals determines that it has accepted for interlocutory appeal under 28 U.S.C. § 1292(b) a case that is no longer suitable for such appeal, it may vacate its order accepting appellate jurisdiction, relinquish jurisdiction, and remand the case to the district court. See United States v. Bear Marine Services, 696 F.2d 1117 (5th Cir. 1983); Paschall v. Kansas City Star Co., 605 F.2d 403 (8th Cir. 1979); Moreau v. Tonry, 554 F.2d 163 (5th Cir. 1977). Disquisition on the question of the constitutionality of Rule B as it is now written would burden the Court without providing a precedent useful to future litigants and probably without materially advancing the ultimate termination of this litigation.

The merits panel may consider events occurring after the motions panel's initial decision. Moreau v. Tonry, 554 F.2d 163, 164 (5th Cir. 1977) (primary issue in case became moot after motions panel's consideration).Accord United States v. 5.96 Acres of Land, 593 F.2d 884, 887 (9th Cir. 1979); Nickert v. Puget Sound Tug Barge Co., 480 F.2d 1039 (9th Cir. 1973); United States v. Salter, 421 F.2d 1393, 1394 (1st Cir. 1970); United States Rubber Co. v. Wright, 359 F.2d 784, 785 (9th Cir. 1966) (per curiam); Molybdenum Corp. v. Kasey, 279 F.2d 216, 217 (9th Cir. 1960) (per curiam).