market folly

Roberto Mignone's hedge fund Bridger Management filed a 13G with the SEC after market close today regarding shares of XenoPort (XNPT). Due to portfolio activity on July 7th, Bridger has disclosed a 6.6% ownership stake in XNPT with 2,000,000 shares. This marks a 42.8% increase in their position size as they previously owned 1,400,000 shares back on March 31st, 2010.

In past coverage, we've seen a divergence of opinion regarding XenoPort amongst hedge funds. Back in May of this year, Steve Cohen's hedge fund SAC Capital showed a XNPT stake while Lee Ainslie's Maverick Capital sold out of the name back in the first quarter. Shares of XenoPort have recently sold off hard from $9 per share down to now around $6.

Prior to founding Bridger Management, Mignone co-founded Blue Ridge Capital with John Griffin. Before that, he worked at Julian Robertson's Tiger Management and Mignone received both his undergraduate degree and MBA from Harvard. Other recent portfolio maneuvering we've seen from Bridger includes adding to their iStar Financial stake. Mignone also in the past has detailed his investment thoughts for 2010 at a hedge fund panel.

Taken from Google Finance, Xenoport is "a biopharmaceutical company focused on developing and commercializing a portfolio of internally discovered product candidates, which utilizes the body’s natural nutrient transport mechanisms to improve the therapeutic benefits of existing drugs".

For more on Roberto Mignone's hedge fund, head to other recent portfolio activity from Bridger.