Leggett & Platt ( LEG) stock was surging after Somnigroup International ( SGI) submitted a proposal to acquire all outstanding common shares of the diversified manufacturer in an all-stock deal.

LEG shares were +12.09% Monday pre-market to $11.50.

Under the proposal, Leggett & Platt shareholders would receive SGI shares with a market value of $12.00 for every one share of common stock they own, based on a fixed exchange ratio to be agreed.

The proposal offers LEG investors a 30.3% premium to the average closing price during the last 30 trading days, and a premium of ~17.0% to the November 28 closing price.

The proposal is subject to the completion of due diligence, the negotiation and execution of definitive transaction documents, and approval by the boards of directors of both companies.

"Leggett & Platt has been an important supplier to our company for many years," said Somnigroup CEO Scott Thompson.