EFTA01450731

William Blair & Company, L LC. MPORTANT DISCLOSURES William Blair is a market maker in the security of ARIAD Pharmaceuticals, Inc. and may have a long or short position. William Blair Intends to seek investment banking compensation in the next three months from the subject company covered in this report. Additional information is available upon request. This report is available in electronic form to registered users via Ft*Docs's at wivivxdoa.com or www.williamblair.com. Please contact us at or consult williamblair.com/Research-a nd-Insights/Equ ity-Research/Coverage.aspx for all disclosures. Y. Katherine Xu attests that 1) all of the views expressed in this research report accurately reflect his/her personal views about any and all of the securities and companies covered by this report, and 2) no part of his/her compensation was, is, or will be related, directly or indirectly, to the specific recommendations or views expressed by him/her in this report. We seek to update our research as appropriate, but various regulations may prohibit us from doing so. Other than certain periodical industry reports, the majority of reports are published at irregular intervals as deemed appropriate by the analyst DOW JONES: 16,221.14 S&P 500: 1,818.32 NASDAQ: 4,104.74 ARIAD Pharmaceuticals, Inc. (ARIA) 326 320 316 310 so 12/31/10 Dec 20, 2010 Dec 20, 2011 Previous Close: $6.43 9/30/13 - PT'$26 10/2. 12 - PT:$28 7/30/12 - I-0 - PT:$25 12130/11 12/31/12 SNoce FattSet .naViiism DS. legend I • Mutt:min. PeetwIPP II • Anel/%I thrOr PT • PrK, TirOr. Current Rating Distribution (as of 11/30/13) Coverage Universe Percent Inv. Banking Relationships* Percent Outperform (Buy) 61 Outperform (Buy) 11 Market Perform (Hold) 35 Market Perform (Hold) 1 Underperform (Sell) 1 Underperform (Sell) 0 'Percentage of companies in each rating category that are investment banking clients, defined as companies for which William Blair has received compensation for investment banking services within the past 12 months. The compensation of the research analyst is based on a variety of factors, including performance of his or her stock recommendations; contributions to all of the firm's departments, including asset management, corporate finance, institutional sales, and retail brokerage; firm profitability; and competitive factors. OTHER IMPORTANT DISCLOSURES sock ratings, price targets, and valuation methodologies: William Blair & Company, LL.0 uses a three-point system to rate stocks. Individual ratings and price targets (where used) reflect the expected performance of the stock relative to the broader market (generally the S&P 500, unless otherwise indicated) over the next 12 months. The assessment of expected performance is a function of near-, intermediate-, and long-term company fundamentals, industry outlook, confidence in earnings estimates, valuation (and our valuation methodology), and other factors. Outperform (0) - stock expected to outperform the broader market over the next 12 months; Market Perform (M) - stock expected to perform 7 I Y. Katherine Xu, Ph.D. CONFIDENTIAL — PURSUANT TO FED. R. GRIM. P. 6(e) DB-SDNY-0 106556 CONFIDENTIAL SDNY_GM_00252740 EFTA01450731