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 increased stock shares of Arch Capital Group Ltd. (NASDAQ:ACGL).

SEC data indicate that these institutions significantly increased their stock shares of Arch Capital Group Ltd. in Q3 2011:

• ARTISAN PARTNERS LIMITED PARTNERSHIP: On 06/30/2011, held 0 shares. On 09/30/2011, held 19,965,099 shares, worth $652,459,435.
• STEADFAST CAPITAL MANAGEMENT LP: On 06/30/2011, held 0 shares. On 09/30/2011, held 1,471,920 shares, worth $48,102,346.
• LORD ABBETT & CO LLC: On 06/30/2011, held 0 shares. On 09/30/2011, held 1,220,970 shares, worth $39,901,300.
• POLAR CAPITAL LLP: On 06/30/2011, held 0 shares. On 09/30/2011, held 568,243 shares, worth $18,570,181.
• MUNDER CAPITAL MANAGEMENT: On 06/30/2011, held 0 shares. On 09/30/2011, held 532,303 shares, worth $17,395,662.

About the company: Arch Capital Group Ltd. is a Bermuda-based insurance and financial services company that provides reinsurance and insurance products on a worldwide basis.

Competitors to Watch: Endurance Specialty Hldgs. Ltd. (NYSE:ENH), Alterra Capital Hldgs. Ltd. (NASDAQ:ALTE), Allied World Assurance Co Hldgs., AG. (NYSE:AWH), PartnerRe Ltd. (NYSE:PRE), W.R. Berkley Corporation (NYSE:WRB), Everest Re Group, Ltd. (NYSE:RE), ACE Limited (NYSE:ACE), Argo Group Intl. Hldgs., Ltd. (NASDAQ:AGII), and Axis Capital Holdings Ltd. (NYSE:AXS).

(Note: Data regarding Arch Capital Group Ltd.’s stock holdings are sourced from whalewisdom.com. All data are assumed to be accurate.)

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