UPDATE: B-MS goes to ImClone shareholders with slightly higher bid, which Icahn rejects

Turning to a hostile stance in its attempts to gain control of Erbitux (cetuximab) partner ImClone Systems, US drug major Bristol-Myers Squibb says that it is raising its bid to $62 a share (up from the $60 it previously offered; Marketletters passim), valuing the remaining 83% of the biotechnology firm's shares at some $4.7 million.

Revealing its intentions late September 22, B-MS also said that it would commence a tender offer for the outstanding stock, therefore taking its its bid directly to shareholders. News of the increase saw ImClone's shares rise 6.9% to $63.51 by close of trading that day, which - prior to a later announcement - analysts believed meant the firm would reject the latest advance especially since its chairman, billionaire investor Carl Icahn has claimed to have a counter bid of $70 per share.

Although the name of the mystery acquirer has not been revealed, there has been speculation that this could be Germany's Merck KGaA, which partners ImClone on Erbitux in non-US markets.