| Top Institutional Holders |
|---|
| Holder | Shares | % Out | Value* | Reported |
|---|
| Deerfield Management | 12,922,070 | 8.70 | 14,731,159 | 31-Mar-2013 | | FMR, LLC | 10,505,000 | 7.07 | 11,975,700 | 31-Mar-2013 | | Lansdowne Partners Limited Partnership | 10,409,190 | 7.00 | 11,866,476 | 31-Mar-2013 | | BVF Inc. | 10,313,435 | 6.94 | 11,757,315 | 31-Mar-2013 | | Price (T.Rowe) Associates Inc | 8,540,000 | 5.75 | 9,735,600 | 31-Mar-2013 | | Vanguard Group, Inc. (The) | 4,208,722 | 2.83 | 4,797,943 | 31-Mar-2013 | | Wellington Management Company, LLP | 3,947,342 | 2.66 | 4,499,969 | 31-Mar-2013 | | BlackRock Institutional Trust Company, N.A. | 1,971,278 | 1.33 | 2,247,256 | 31-Mar-2013 | | Allianz Asset Management AG | 1,962,085 | 1.32 | 2,236,776 | 31-Mar-2013 | | Principal Financial Group, Inc. | 1,879,093 | 1.26 | 2,142,166 | 31-Mar-2013 |
|
| Holder | Shares | % Out | Value* | Reported |
|---|
| Fidelity Select Portfolios - Biotechnology | 6,380,800 | 4.29 | 7,274,112 | 31-Mar-2013 | | Price (T.Rowe) New Horizons Fund | 5,280,110 | 3.55 | 6,019,325 | 31-Mar-2013 | | Vanguard Extended Market Index Fund | 2,167,862 | 1.46 | 1,430,788 | 31-Dec-2012 | | Price (T.Rowe) Health Sciences Fund | 2,012,800 | 1.35 | 2,294,592 | 31-Mar-2013 | | Variable Insurance Products Fund-Growth Portfolio | 1,808,300 | 1.22 | 2,061,462 | 31-Mar-2013 | | Fidelity Advisor Equity Growth Fund | 1,427,700 | 0.96 | 1,627,578 | 31-Mar-2013 | | Vanguard Total Stock Market Index Fund | 1,317,541 | 0.89 | 869,577 | 31-Dec-2012 | | General American Investors Co | 789,211 | 0.53 | 899,700 | 31-Mar-2013 | | Principal Small Cap Blend Fund | 577,712 | 0.39 | 658,591 | 31-Mar-2013 | | Fidelity Growth Discovery Fund | 480,700 | 0.32 | 547,998 | 31-Mar-2013 |
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View Transactions for Insiders & Institutional Holders Value shown is computed using the security's price on the report date given. Currency in USD. |