The case is SpeechNow.org v. FEC (en banc) (unanimous):
The contribution limits of 2 U.S.C. § 441a(a)(1)(C) and 441a(a)(3) violate the First Amendment by preventing plaintiffs from donating to SpeechNow in excess of the limits and by prohibiting SpeechNow from accepting donations in excess of the limits. We should be clear, however, that we only decide these questions as applied to contributions to SpeechNow, an independent expenditure-only group. Our holding does not affect, for example, § 441a(a)(3)’s limits on direct contributions to candidates.
Sounds quite right to me, and entirely consistent with the Court’s past jurisprudence on the right to expressive association, which goes back 50 years to the NAACP cases. The right to speak, about candidates, ballot measures, and other matters, must include the right of people to pool their resources in order to speak effectively — not just the right to speak by oneself, or using just one’s own resources. But contributions to candidates are a different matter, for reasons I discuss in Part III of this article.
The court also upheld various organizational, recordkeeping, and reporting requirements: “SpeechNow, as we have said, intends to comply with the disclosure requirements applicable to those who make independent expenditures but are not organized as political committees…. Because SpeechNow intends only to make independent expenditures, the additional reporting requirements that the FEC would impose on SpeechNow if it were a political committee are minimal…. Nor do the organizational requirements that SpeechNow protests, such as designating a treasurer and retaining records, impose much of an additional burden upon SpeechNow, especially given the relative simplicity with which SpeechNow intends to operate.”