A developer of medicinal-grade fish oil for the treatment of patients with too much fat in their blood. Amarin is attracting increasing investor attention as it gets ready to submit AMR101 for FDA approval later this quarter. The company has also been mentioned as a potential takeover target.Year to date performance: + 55% Performance since June 30: -12% Expo Capital Management built a new 3 million-share position in Amarin in the second quarter, while Healthcor joined the company's roster of shareholders by acquiring 2 million shares. Steven Cohen's SAC Capital added another 2.9 million shares to its existing position. Orbimed Advisors appears to have taken advantage of the heightened interest in Amarin to lighten its stake in the company by 4.7 million shares. Hutchin Hill Capital and David Knott Partners were also sellers during the quarter.