Graphic Packaging Holding Company Investigated by the Portnoy Law Firm

LOS ANGELES, March 16, 2026 (GLOBE NEWSWIRE) -- The Portnoy Law Firm advises Graphic Packaging Holdings Company, (“Graphic Packaging" or the "Company") (NYSE:GPK) investors that the firm has initiated an investigation into possible securities fraud, and may file a class action on behalf of investors.

Investors are encouraged to contact attorney Lesley F. Portnoy, by phone 844-767-8529 or email: lesley@portnoylaw.com, to discuss their legal rights, or join the case via https://portnoylaw.com/graphic-packaging-holding-company/. The Portnoy Law Firm can provide a complimentary case evaluation and discuss investors’ options for pursuing claims to recover their losses.

An investigation has been launched into whether the board of directors at Graphic Packaging grossly mismanaged the Company or breached its fiduciary duties to shareholders following several executive shifts. This probe follows a December 2025 letter issued by a shareholder holding 4.2% of the Company’s stock, which was written in response to the news that Michael Doss would be replaced as CEO by Robbert E. Rietbroek. Only weeks after this leadership transition was announced, the Executive Vice President and General Counsel for the Company also departed from her positions.

The Portnoy Law Firm represents investors in pursuing claims caused by corporate wrongdoing. The Firm’s founding partner has recovered over $5.5 billion for aggrieved investors. Attorney advertising. Prior results do not guarantee similar outcomes.

Lesley F. Portnoy, Esq.

Admitted CA, NY and TX Bar

lesley@portnoylaw.com

310-692-8883

www.portnoylaw.com

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