Activist investors disclose stake changes in five companies

4 articles · Updated · Barron's · May 1

SEC 13D filings from April 23-29 showed Horizon Kinetics increased Miami International to 12.2%, Perceptive raised MeiraGTx to 12.6%, and Gamco lifted Monro to 10.7%.
Gamco cut Nathan's Famous to 11.8%, while Castle Creek sold Primis Financial down to 4.4%, dropping below the 5% reporting threshold; Horizon's Eric Sites also joined Miami International's board.
The disclosures cover holdings above 5% and subsequent changes. In 2026, shares were up about 9.1% for Miami International and Nathan's, 14.6% for MeiraGTx, 11.8% for Primis, while Monro was down 15%.

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