Insiders are generally long-term investors due to restriction in making short-term profits. In contrast, wealth management institutions always have short-term investment. Wall St. Watchdog reveals information regarding the insiders and institutions which recently decreased stock shares of Cubist Pharmaceuticals Inc. (NASDAQ:CBST).

SEC data indicate these insiders have sold Cubist Pharmaceuticals Inc.’s stock since 06/30/2011:

• Gilman Steven C: act as EVP & Chief Scientific Officer. On 10/26/2011, sold 71,250 shares, worth $2,757,400.
• Vetticaden Santosh: act as SVP & Chief Medical Officer. On 10/26/2011, sold 55,000 shares, worth $2,123,000.
• Stea Gregory: act as SVP, Commercial Operations. On 10/26/2011, sold 50,938 shares, worth $1,960,600.

SEC data indicate that these institutions significantly reduced their stock shares of Cubist Pharmaceuticals Inc. in Q3 2011:

• HEALTHCOR GROUP LLC: On 06/30/2011, held 1,900,000 shares, worth $68,381,000. On 09/30/2011, held 0 shares.
• SABRETOOTH CAPITAL MANAGEMENT LLC: On 06/30/2011, held 255,000 shares, worth $9,177,450. On 09/30/2011, held 0 shares.
• LOEB ARBITRAGE MANAGEMENT LP: On 06/30/2011, held 112,894 shares, worth $4,063,055. On 09/30/2011, held 0 shares.
• PERCEPTIVE ADVISORS LLC: On 06/30/2011, held 100,000 shares, worth $3,599,000. On 09/30/2011, held 0 shares.
• PERELLA WEINBERG PARTNERS CAPITAL MANAGEMENT LP: On 06/30/2011, held 82,390 shares, worth $2,965,216. On 09/30/2011, held 0 shares.

About the company: Cubist Pharmaceuticals, Inc. is a drug company that discovers, develops, and commercializes novel drugs to treat infections. The Company’s lead product is a unique agent with bactericidal activity that addresses the critical need for new antibiotics with potent activity against life threatening infections.

Competitors to Watch: Optimer Pharmaceuticals, Inc. (NASDAQ:OPTR), Merck & Co., Inc. (NYSE:MRK), Teva Pharmaceutical Industries Ltd (NASDAQ:TEVA), Theravance, Inc. (NASDAQ:THRX), Pfizer Inc. (NYSE:PFE), Novartis AG (NYSE:NVS), The Medicines Company (NASDAQ:MDCO) and Abbott Laboratories (NYSE:ABT).

(Note: Data regarding Cubist Pharmaceuticals Inc.’s stock holdings are sourced from whalewisdom.com. All data are assumed to be accurate.)

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