Carl Icahn is showing his fangs. In a statement, ImClone’s chairman says Bristol-Myers Squibb’s $4.5 billion offer is way too low. He then maintains the bid was motivated, in part, because ImClone is developing a drug that may compete with Erbitux, the cancer med the two drugmakers jointly market. But Bristol may not have rights to this new drug. Bristol, you may recall, already owns 17 percent of ImClone.

Here’s the fun part: Carl, essentially, accuses Bristol ceo Jim Cornelius of trying to pull a fast one. The statement says that Icahn “was disturbed that one of the directors on the ImClone Board, who is the Bristol-Myers designee, was privy to the information discussed at previous meetings concerning the potential separation of ImClone into two separate components and how this restructuring might enhance stockholder value. Accordingly, the Board is reviewing whether Bristol-Myers had access to confidential information concerning ImClone and its pipeline.”

We love hardball tactics, especially those put on display for vicarious consumption. And who knows? Maybe Carl will turn around and buy up Bristol shares. After all, the stock is well below the $32 range it reached at this time last summer, the highest price reached in years. UPDATE: A Bristol spokesman tells Reuters the drugmaker believes it has rights to the experimental cancer drug, and denies acting on confidential info.