with whom The Chief Justice joins, dissenting.
I substantially agree with the reasoning of the Court of Appeals for the Eighth Circuit in this case. 545 F. 2d 599. Accordingly, I would affirm the judgment before us.
The Court today seems to concede that Minnesota’s statutory modification of the appellee’s substantive obligations under its collective-bargaining agreement would be pre-empted by the federal labor laws if Congress had not somehow indicated that the State was free to impose this particular modification. Ante, at 513-514. The Court finds such an indication implicit in Congress’ failure to undertake substantive regulation of pension plans when it enacted the So-called Disclosure Act of 1958. I do not believe, however, that inferences drawn largely from what Congress did not do in enacting the Disclosure Act are sufficient to override the fundamental policy of the national labor laws to leave undisturbed “the parties’ solution of a problem which Congress has *516required them to negotiate in good faith toward solving . . . Teamsters v. Oliver, 358 U. S. 283, 296.