BOSTON ( TheStreet) -- Hedge funds peeled back the curtain this week to reveal a bit about what biotech stocks they were buying and selling during the second quarter. Funds that manage more than $100 million are required to disclose their equity holdings, options and convertible debt on a Form 13F filed with the Securities and Exchange Commission within 45 days of the end of a quarter. Funds aren't required to report short positions betting on declines. Because these disclosures are lagging, it's also not possible to tell what hedge funds have done with these biotech stocks since June 30, when the second quarter ended. Still, combing through 13F filings can give individual investors some inkling into where professional investors are placing their biotech investment capital. On the following pages, you'll find a snapshot of 11 biotech stocks with significant hedge fund buying and selling during the second quarter.