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 American Tower Corp. (NYSE:AMT).

SEC data indicate that these institutions significantly increased their stock shares of American Tower Corp. in Q3 2011:

• YORK CAPITAL MANAGEMENT GLOBAL ADVISORS, LLC: On 06/30/2011, held 0 shares. On 09/30/2011, held 1,273,400 shares, worth $68,508,920.
• FARALLON CAPITAL MANAGEMENT LLC: On 06/30/2011, held 0 shares. On 09/30/2011, held 730,000 shares, worth $39,274,000.
• COBALT CAPITAL MANAGEMENT INC: On 06/30/2011, held 0 shares. On 09/30/2011, held 700,000 shares, worth $37,660,000.
• PUBLIC EMPLOYEES RETIREMENT ASSOCIATION OF COLORADO: On 06/30/2011, held 0 shares. On 09/30/2011, held 592,803 shares, worth $31,892,801.
• TEACHERS RETIREMENT SYSTEM OF THE STATE OF KENTUCKY: On 06/30/2011, held 0 shares. On 09/30/2011, held 574,199 shares, worth $30,891,906.

About the company: American Tower Corporation owns, operates, and develops wireless communications and broadcast towers in the United States. The Company leases antennae sites on multi-tenant towers for a diverse range of wireless communications industries, including personal communications services, paging, and cellular. American Tower also offers a variety of network development services.

Competitors to Watch: Crown Castle Intl. Corp. (NYSE:CCI), SBA Communications Corp. (NASDAQ:SBAC), Syniverse Holdings, Inc. (NYSE:SVR), AT&T Inc. (NYSE:T), Neustar, Inc (NYSE:NSR), WPCS International Inc. (NASDAQ:WPCS), Telephone & Data Systems, Inc. (NYSE:TDS), Sprint Nextel Corporation (NYSE:S), and Verizon Communications Inc. (NYSE:VZ).

(Note: Data regarding American Tower Corp.’s stock holdings are sourced from whalewisdom.com. All data are assumed to be accurate.)

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