ImClone Systems Inc. returned the volley against the Bristol-Myers Squibb Co.'s $60 per-share bid for the biotech, calling the bid too low and noting that it already was considering splitting itself into two companies to maximize shareholder value.

ImClone, of New York, issued a statement that said it has formed a committee to study the offer and hired advisors to help, but it stated that the board's preliminary view "is that the offer substantially undervalues ImClone."

The company said the board has been discussing dividing the firm into two companies, one for its highly profitable Erbitux franchise and the other for its pipeline business.

While noting that the pipeline products are in a variety of stages, the board said it believes that pipeline "may be extremely valuable and significantly increase stockholder value as a separate business."

Last week BMS, which already owns more than 16 percent of ImClone, offered $44 billion for the remainder, a bid a chorus of analysts called too low. (See BioWorld Today, Aug. 1, 2008.)

Carl Icahn, ImClone chairman, stated his opposition to the offer, and also noted that he was "disturbed" because an unnamed ImClone director who is the BMS board designee "was privy to the information discussed at previous meetings concerning the potential separation of ImClone into two separate components."

The ImClone board, he said, is reviewing whether BMS had access to confidential information concerning ImClone and its pipeline.

Icahn also noted that ImClone has a pipeline antibody, IMC-11F8, under development, which could, if approved, compete against Erbitux and that BMS "may have no rights to market that product" under its agreement with ImClone.