We agree with the result of the denial arbitration, but disagree with the reason for its denial. Since the suit for arbitration was due to be denied, we affirm.
The crux of this case is whether parties can contractually agree to arbitrate representation questions. If the agreement provides for such arbitration, concurrent jurisdiction of the National Labor Relations Board will not deprive the parties of their bargain. Amalgamated Ass’n. of Street, Electric Ry. & Motor Coach Employees of America v. Lockridge, 403 U.S. 274, 301, 91 S.Ct. 1909, 29 L.Ed.2d 473 (1971); Carey v. Westinghouse Elec. Corp., 375 U.S. 261, 268, 84 S.Ct. 401, 11 L.Ed.2d 320 (1964); Smith v. Evening News Ass’n, 371 U.S. 195, 197, 83 S.Ct. 267, 9 L.Ed.2d 246 (1962). It is indeed an unusual contract which will provide for arbitrable issues dealing with accretions of employees by other bargaining units, or, as would be postulated here, the accretion of a separate unit by another unit. Such questions are principally for the Board. But a district court and an arbitrator are not preempted in a 301 action by such considerations if the contract’s arbitration provisions are “arguably” applicable to the dispute and the facts of the dispute convince the district court that the parties had indeed agreed to arbitrate. International Union of Operating Engineers, Local 150, AFL-CIO v. Flair Builders, Inc., 406 U.S. 487, 92 S.Ct. 1710, 32 L.Ed.2d 248 (1972); Jacksonville Newspaper Printing Pressmen & Assistants’ Union No. 57 v. Florida Publishing Co., 468 F.2d 824 (5th Cir., 1972); Southwestern Bell Tel. Co. v. Communication Workers of America, 454 F.2d 1333 (5th Cir., 1971); Lodge 1327, International Ass’n of Machinists & Aerospace Workers, AFL-CIO v. Fraser & Johnston Co., 454 F.2d 88 (9th Cir., 1971). The representational nature of the question alone is an insufficient basis to deprive parties of contracted for arbitration. Carey v. Westinghouse Elec. Corp.,
supra. Accommodation of arbitration with the Board also presents no bar to such an order. Lodge 1327, International Ass’n of Machinists & Aerospace Workers, AFL-CIO v. Fraser & Johnston Co.,
supra. Where a unit clarification petition or unfair labor practice charge is in progress, whether before or after an arbitration decision, the Board has demonstrated its ability to make its own accommodation to the arbitration process. Lodge No. 12, etc. v. Cameron Iron Works, 257 F.2d 467 (5th Cir., 1958); Spielberg Mfg. Co., 112 N.L.R.B. 1080 (1955); Collyer Insulated Wire, 192 N.L.R.B. 150 (1971). This again presents no reason to deprive the parties of their bargain. But the question of substantive arbitrability in a Section 301 case is for the court. Atkinson v. Sinclair Refining Co., 370 U.S. 238, 241, 82 S.Ct. 1318, 8 L.Ed.2d 462 (1962); accord,
United Steel Workers v. Warrior & Gulf Navigation Co., 363 U.S. 574, 582, 80 S.Ct. 1347, 4 L.Ed.2d 1409 (1960); United Steel Workers v. American Mfg. Co., 363 U.S. 564, 80 S.Ct. 1343, 4 L.Ed.2d 1403 (1960); United Steel Workers v. Enterprise Wheel
& Car Corp., 363 U.S. 593, 80 S.Ct. 1358, 4 L.Ed.2d 1424 (1960); accord, John Wiley & Sons, Inc. v. Livingston, 376 U.S. 543, 84 S.Ct. 909, 11 L.Ed.2d 898 (1964). Compare International Union of Operating Engineers, Local 150, AFL-CIO v. Flair Builders, Inc.,
supra. We must therefore determine both whether the parties agreed to arbitrate and what is-uses were included in the agreement under this circuit’s previously announced standard of arguable arbitrability.
See Lodge No. 12, etc. v. Cameron Iron Works, Inc.,
supra; Communication Workers of America v. Southwestern Bell Tel. Co., 415 F.2d 35 (5th Cir., 1969); Southwestern Bell Tel. Co. v. Communication Workers of America, 454 F.2d 1333 (5th Cir., 1971).
But even a standard of arguable arbitrability which favors arbitration in the doubtful case, see United Steel Workers v. Warrior & Gulf Navigation Co., supra, cannot justify our con