In the case of Atkinson et al. v. Sinclair Refining Co., 1961, the United States Supreme Court ruled in favor of Sinclair Refining Co., reversing a lower court's decision that had favored Atkinson and his fellow plaintiffs (union members). The dispute arose when union workers picketed at sites where non-union contractors were working for Sinclair, despite an existing no-strike agreement between the union and company. The issue before the court was whether such secondary boycott activities were protected by federal labor laws or if they violated a contractual no-strike clause agreed upon by both parties. In its ruling, the Supreme Court held that these actions did indeed violate this clause as it constituted a breach of contract under common law principles. Therefore, unions could be liable for damages caused to employers due to unauthorized strikes or similar disruptive activities even though they are not directly involved in disputes with those employers.

In the dissenting opinion for Atkinson et al. v. Sinclair Refining Co., Justice Frankfurter disagreed with the majority's interpretation of Section 301(a) of the Labor Management Relations Act, arguing that it was not intended to provide a federal forum for all contract disputes between employers and labor unions. He believed that Congress had only meant to allow federal courts jurisdiction over cases involving violations of collective bargaining agreements, not those concerning internal union affairs or secondary boycotts as in this case. Furthermore, he argued that even if such jurisdiction existed under Section 301(a), it should be limited by traditional principles of equity jurisprudence which would require exhaustion of intra-union remedies before resorting to litigation. In his view, allowing immediate access to federal courts could undermine internal union governance and disrupt labor-management relations.