Ownership Submission
FORM 4
Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).
UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940
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(Print or Type Responses)
1. Name and Address of Reporting Person *
TAICLET JAMES D JR
  2. Issuer Name and Ticker or Trading Symbol
AMERICAN TOWER CORP /MA/ [AMT]
5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
Chairman, President and CEO
(Last)
(First)
(Middle)
116 HUNTINGTON AVENUE
3. Date of Earliest Transaction (Month/Day/Year)
03/10/2014
(Street)

BOSTON, MA 02116
4. If Amendment, Date Original Filed(Month/Day/Year)
6. Individual or Joint/Group Filing(Check Applicable Line)
_X_ Form filed by One Reporting Person
___ Form filed by More than One Reporting Person
(City)
(State)
(Zip)
Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1.Title of Security
(Instr. 3)
2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code
(Instr. 8)
4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 and 5)
5. Amount of Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 3 and 4)
6. Ownership Form: Direct (D) or Indirect (I)
(Instr. 4)
7. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V Amount (A) or (D) Price
Common Stock 03/10/2014   M   11,888 A $ 0 11,888 D  
Common Stock 03/10/2014   F   5,606 D $ 81.18 6,282 D  
Common Stock 03/10/2014   M   14,770 A $ 0 21,052 D  
Common Stock 03/10/2014   F   6,965 D $ 81.18 14,087 D  
Common Stock 03/11/2014   M   14,630 A $ 0 28,717 D  
Common Stock 03/11/2014   F   6,794 D $ 81.7 21,923 D  
Common Stock               1,630 I By minor children (1)
Common Stock               100,041 (2) I By GRAT

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)
1. Title of Derivative Security
(Instr. 3)
2. Conversion or Exercise Price of Derivative Security 3. Transaction Date (Month/Day/Year) 3A. Deemed Execution Date, if any (Month/Day/Year) 4. Transaction Code
(Instr. 8)
5. Number of Derivative Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4, and 5)
6. Date Exercisable and Expiration Date
(Month/Day/Year)
7. Title and Amount of Underlying Securities
(Instr. 3 and 4)
8. Price of Derivative Security
(Instr. 5)
9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s)
(Instr. 4)
10. Ownership Form of Derivative Security: Direct (D) or Indirect (I)
(Instr. 4)
11. Nature of Indirect Beneficial Ownership
(Instr. 4)
Code V (A) (D) Date Exercisable Expiration Date Title Amount or Number of Shares
Restricted Stock Units (3) 03/10/2014   M     11,888   (4)   (4) Common Stock 11,888 $ 0 0 D  
Restricted Stock Units (3) 03/10/2014   M     14,770   (5)   (5) Common Stock 14,770 $ 0 14,769 D  
Restricted Stock Units (3) 03/11/2014   M     14,630   (6)   (6) Common Stock 14,630 $ 0 43,888 D  
Option to Purchase Common Stock $ 81.18 03/10/2014   A   303,235     (7) 03/10/2024 Common Stock 303,235 $ 0 303,235 D  
Restricted Stock Units (3) 03/10/2014   A   55,433     (8)   (8) Common Stock 55,433 $ 0 55,433 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
TAICLET JAMES D JR
116 HUNTINGTON AVENUE
BOSTON, MA 02116
  X     Chairman, President and CEO  

Signatures

 /s/ Mneesha O. Nahata, as attorney-in-fact   03/12/2014
**Signature of Reporting Person Date

Explanation of Responses:

* If the form is filed by more than one reporting person, see Instruction 4(b)(v).
** Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1) The reporting person disclaims beneficial ownership in shares owned by minor children.
(2) 100,041 shares were previously reported as directly beneficially owned. These shares were contributed to a grantor retained annuity trust ("GRAT") on December 20, 2013.
(3) Each Restricted Stock Unit (RSU) respresents a contingent right to receive one share of Common Stock.
(4) This RSU was granted on March 10, 2010 pursuant to the 2007 Equity Incentive Plan, and vests in 25% cumulative annual increments beginning March 10, 2011. This Form 4 reflects the vesting of this RSU on March 10, 2014 as to 100% of the original grant amount.
(5) This RSU was granted on March 10, 2011 pursuant to the 2007 Equity Incentive Plan, and vests in 25% cumulative annual increments beginning March 10, 2012. This Form 4 reflects the vesting of this RSU on March 10, 2014 as to 75% of the original grant amount.
(6) This RSU was granted on March 11, 2013 pursuant to the 2007 Equity Incentive Plan, and vests in 25% cumulative annual increments beginning March 11, 2014. This Form 4 reflects the vesting of this RSU on March 11, 2014 as to 25% of the original grant amount.
(7) This option was granted on March 10, 2014 pursuant to the 2007 Equity Incentive Plan and is exercisable in 25% cumulative annual increments beginning March 10, 2015.
(8) This RSU was granted on March 10, 2014 pursuant to the 2007 Equity Incentive Plan and vests in 25% cumulative annual increments beginning March 10, 2015.

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