To go public or merge is one of the enduring questions of biotech: companies and management are driven by vision and ego to remain independent, but the logic of overly small technology bases and excess infrastructure argues for consolidation. Given the choice between going public - and going it alone - or merging into a stronger combined entity, ChemGenics chose to merge with Millennium (MLNM).

ChemGenics said its decision wasn't driven by its effort to penetrate the IPO market: the company had filed to go public in December. According to the company, the market's initial response to the IPO was strong, and the merger was not simply an alternative to a watered-down public deal. "The market from the time we filed was very healthy looking at price and comparables," said Alan Crane, ChemGenics's vice president of business development. "Our comparable went up 30 percent from the time we filed."