Markel Group (MKL) faces activist pressure from Jana Partners, which called on the company to divest its Markel Ventures unit and launch a $2 billion tender offer to address what it calls years of persistent undervaluation.

In a letter to the board on Thursday, Jana said Markel's years of weak shareholder returns can no longer be explained by an underperforming insurance segment or by the market failing to understand its "unique flywheel" of combining insurance and Ventures.

Markel's decision to acquire "a disparate collection" of Ventures businesses that public equity investors would not have funded on similar terms is weighing on its improving specialty insurance franchise, Jana said.

Markel didn't immediately reply to a request for comment from MT Newswires.

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