UPDATE 3-ImClone says hires JP Morgan to weigh options

(Adds JP Morgan comment, paragraph 11; closing stock prices, paragraph 12)

By Jessica Hall

PHILADELPHIA, Aug 14 (Reuters) - Biotechnology company ImClone Systems Inc, which rebuffed a $60-per-share takeover offer from Bristol-Myers Squibb Co (BMY.N), said on Thursday it hired JP Morgan Chase & Co (JPM.N) as its financial adviser.

JP Morgan will help ImClone IMCL.O study Bristol's offer in more detail, and weigh a possible plan to split ImClone into two businesses, sources familiar with the situation said.

Formal talks between ImClone and Bristol have not yet begun, sources said.

Earlier this month, ImClone rejected as too low Bristol's offer to acquire the shares of ImClone it did not already own in a deal that valued the company at $5.2 billion.

ImClone, meanwhile, said its board had been discussing the possibility of separating its Erbitux cancer treatment business and its drug-development pipeline operations.

Erbitux is approved for colorectal and head and neck cancer in the United States and Canada, while a recent approval for the drug in Japan and new lung cancer data are expected to drive sales.

ImClone said it believed the pipeline business "may be extremely valuable and significantly increase stockholder value as a separate business."

Activist investor Carl Icahn, chairman of ImClone and a large shareholder of the company, had said he opposed Bristol-Myers' offer because he believes it "greatly undervalues the company."

Also up for debate is an ImClone antibody, IMC-11F8, that is under development. If approved for sale, ImClone has said the antibody "might have a significant competitive effect on Erbitux," and Bristol-Myers may have no rights to market that product.

Bristol previously termed its offer for ImClone "full and fair" and said it believed it has rights to the follow-on drug to Erbitux.

JP Morgan confirmed that it had been hired as ImClone's financial adviser. Bristol, which had hired Citigroup Inc (C.N), Morgan Stanley (MS.N) and Credit Suisse (CSGN.VX) as its advisers, declined to comment on Thursday.

ImClone shares fell 20 cents to close at $63.75 on Nasdaq, while Bristol shed 10 cents to close at $21.88 on the New York Stock Exchange. (Additional reporting by Toni Clarke in Boston; Editing by Lisa Von Ahn, Maureen Bavdek, Gary Hill)