OSI, Astellas deal

Astellas began an unsolicited tender offer to acquire OSI for $52 per share, or about $3.5 billion. The price is a 40% premium to OSI's close of $37.02 on Feb. 26, the last day of trading before the offer was announced. Astellas said it has made attempts since January 2009 to acquire OSI, including an oral proposal of $52 per share made to OSI last month. OSI said it had privately rejected the February proposal and offered to provide Astellas with non-public information about OSI. OSI also said its board will review the newly proposed tender offer and advised its shareholders to take no action at this time. Citigroup is advising Astellas. The offer expires at midnight on March 31.

Additionally, Astellas filed suit in the Delaware Court of Chancery accusing OSI's board of breach of fiduciary duty. Astellas is seeking an injunction preventing the board from applying OSI's poison pill provision. Under the provision, if any shareholder acquires 17.5% or more of the outstanding shares, other existing shareholders will be able to purchase additional shares at a 50% discount to the market price. ...