Questcor stockholders will receive $30 per share in cash and 0.897 Mallinckrodt shares for each Questcor share they own, for a total consideration of approximately $86.10 per Questcor share. Questcor is based in California.
The companies put the transaction's total value at about $5.6 billion.
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After the deal closes, Mallinckrodt shareholders will own about 50.5 percent and former Questcor shareholders will own about 49.5 percent of the combined company's stock. Both companies' boards unanimously approved the transaction.
The combined company will be headed by Mallinckrodt President and CEO Mark Trudeau. Mallinckrodt's board will expand by three members to 12 directors.
Questcor's stock rose by more than 30 percent in Monday premarket trading. (Click here for the latest quote.)
—By The Associated Press