Updated from Wednesday, Oct. 1Investors will wait longer yet for affirmation or more information about the mystery bidder for ImClone Systems ( IMCL), according to a statement late Wednesday. ImClone Chairman Carl Icahn said in a release that the mystery bidder for ImClone has made a proposal not subject to financing or further due diligence. Negotiations are reportedly underway and the company has requested that ImClone not reveal the bidder's name until negotiations are complete. The Wall Street Journal reported earlier Wednesday evening that Eli Lilly ( LLY) was the mystery bidder "in advanced talks" to buy ImClone for $70 a share. The deal, yet to be confirmed by either company, would value ImClone at $6.1 billion. By acquiring ImClone, Lilly would gain a marketed cancer drug, Erbitux, but just as important -- perhaps even more important to Lilly -- is gaining control over ImClone's know-how in developing and manufacturing biologic (i.e. biotech) drugs. A further plus for Lilly is ImClone's pipeline of five cancer drugs in various stages of early and mid-stage clinical trials. This would beef up Lilly's internal cancer drug pipeline. Alimta, Lilly's biggest cancer drug that is approved for the treatment of non-small cell lung cancer, reported sales of $522 million in the first six months of 2008, a 32% increase over the first six months of 2007. Alimta and Erbitux may not necessarily compete in lung cancer because Alimta cannot be used to treat patients with so-called squamous form of non-small cell lung cancer. Squamous cell is one of the most common forms of non-small cell lung cancer. Erbitux, however, is likely to be used in patients with squamous non-small cell lung cancer, based on the phase III clinical data presented earlier this year. The pre-announced due diligence period for the mystery bidder expired on Sunday, and ImClone said on Monday that the potential suitor would make up its mind by Wednesday. The company would either make a firm offer or withdraw by that deadline, and its name would be divulged if it withdrew its proposal. Bristol-Myers Squibb ( BMY) last week announced its intent to go hostile with its own bid for the company, raising it to $62 a share and going directly to shareholders. ImClone's Icahn dismissed the hostile tender offer as "misleading" and "absurd." ImClone is best known for its Erbitux cancer drug, which Bristol-Myers sells in the U.S. German company Merck KGaA sells the drug in Europe. ImClone shares were up $2.69, or 4.3%, at $65.09 in after-hours trading, while Lilly's shares edged down 31 cents, or 0.7%, at $43.72. Rival bidder Bristol-Myers shares were up 25 cents, or 1.2%, at $20.79 in the post-market.