Ebb & Flow

Savvy investors rarely use significant public events - FDA panel meetings, major conferences - to buy stocks. Smart money makes its bets long before the news hits the wire. Such front running was underscored at last week's American Society of Clinical Oncology meeting in San Francisco, which by many measures was well attended and newsy, but did little for the valuations of the companies presenting data.

The real price moves came in the weeks prior to the meeting, as money managers readied their portfolios for the upcoming presentations. Of the 15 companies that presented efficacy data at ASCO, 11 traded up in the month prior to the meeting, with five of the 11 moving up 20% or more (see "AS-is-CO"). The BioCentury 100 traded down 2.4% during the same period (April 13-May 11). ...