A South Windsor manufacturer, Keystone Paper & Box Co., has been acquired by a New York packaging company.
Keystone was purchased by Mill Rock Packaging Partners LLC, which is based in New York City.
Keystone manufacturers custom folding cartons for consumer and healthcare customers.
Mill Rock Packaging is a portfolio company of Mill Rock Capital, a private equity firm that invests in the consumer packaging industry.
Mill Rock Packaging announced the deal Monday. It is Mill Rock’s fourth acquisition since it was formed in 2020.
Keystone’s management will remain with the company, according to Mill Rock. Terms of the deal were not disclosed.
“I am very proud of what we’ve achieved at Keystone since our founding by my grandfather,” said Jim Rutt, president of Keystone. “Through our partnership with Mill Rock Packaging, our customers will gain access to high-quality production facilities in the Midwest and West Coast.”
