## Facts

- Francis A. Rondeau accumulated shares of Mosinee Paper Corporation and crossed the 5% beneficial ownership threshold that triggers disclosure under § 13(d) of the Securities Exchange Act of 1934 (Williams Act).
- Rondeau failed to file the required Schedule 13D within 10 days; he filed roughly three months late.
- He conceded a statutory violation but asserted it resulted from unfamiliarity with securities laws, not an attempt to mislead, and that the issuer and shareholders suffered no harm.
- The record reflected no concrete effort by Rondeau to obtain control; after learning of the obligation, he made the required disclosure and indicated willingness to update material changes.
- Mosinee sued, characterizing the late filing as a fraudulent scheme, and sought equitable relief including (i) restrictions on voting or pledging the shares, (ii) an injunction against further purchases, and (iii) forced divestiture.

## Issues

1. Whether a private plaintiff seeking injunctive relief for a § 13(d) violation must satisfy traditional equitable requirements, including proving irreparable harm.
2. Whether a late but cured Schedule 13D filing, without evidence of a control effort or ongoing threat, constitutes sufficient harm to justify extraordinary equitable remedies such as voting restrictions or divestiture.

## Decision

- The Supreme Court reversed the Seventh Circuit and reinstated the district court’s denial of equitable relief.
- The Court held that a private litigant must show irreparable harm, consistent with traditional principles of equity, to obtain an injunction based on a § 13(d) violation.
- On these facts, Mosinee did not establish irreparable injury; the late filing was treated as a technical default that had been cured by subsequent disclosure.
- The Court rejected divestiture and related restrictions as unwarranted where disclosure had been made and there was no showing of continuing injury or imminent control-related misconduct.

## Legal Principles

- Traditional equitable prerequisites govern private suits seeking injunctive relief for § 13(d) violations; courts do not presume entitlement to an injunction from a statutory filing violation alone.
- A cured, nonwillful delay in § 13(d) disclosure, without an ongoing threat of harm or an active control attempt, generally does not support extraordinary equitable remedies such as forced divestiture or voting restraints.
- Where alleged shareholder injury stems from trading decisions made before disclosure, damages actions may provide an adequate remedy, weighing against equitable relief.
- The Williams Act’s disclosure regime is designed to inform the market while maintaining neutrality in corporate control contests; it does not convert issuers into automatic enforcers entitled to coercive equitable remedies absent proof of irreparable harm.

## Conclusion

The Court required private plaintiffs seeking injunctions for § 13(d) violations to prove irreparable harm under traditional equity standards, and it denied divestiture and other restraints where the filer’s delay was cured by disclosure and no ongoing injury or control effort was shown.


Rondeau v. Mosinee Paper Corp., 422 U.S. 49 (1975)