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 *
Meaney William L
   2. Issuer Name and Ticker or Trading Symbol
IRON MOUNTAIN INC [IRM] 		5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)
__X__ Director _____ 10% Owner
__X__ Officer (give title below) _____ Other (specify below)
President and CEO
(Last)
(First)
(Middle)
C/O IRON MOUNTAIN INCORPORATED, ONE FEDERAL STREET		 3. Date of Earliest Transaction (Month/Day/Year)
02/19/2019
(Street)

BOSTON, MA 02110		 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, par value $.01 per share 02/19/2019   M   25,105 (1) A $ 0 155,007 D  
Common Stock, par value $.01 per share 02/19/2019   F   11,146 D $ 35.39 143,861 D  
Common Stock, par value $.01 per share 02/19/2019   M   18,225 (2) A $ 0 162,086 D  
Common Stock, par value $.01 per share 02/19/2019   F   8,091 D $ 35.39 153,995 D  
Common Stock, par value $.01 per share 02/19/2019   M   52,113 (3) A $ 0 206,108 D  
Common Stock, par value $.01 per share 02/19/2019   F   22,783 D $ 35.39 183,325 D  
Common Stock, par value $.01 per share 02/19/2019   S   8,621 (4) D $ 35.28 (5) 174,704 D  

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 (6) 02/19/2019   M     25,105   (7)   (7) Common Stock 25,105 $ 0 0 D  
Restricted Stock Units (6) 02/19/2019   M     18,225   (8)   (8) Common Stock 18,225 $ 0 18,280 D  
Performance Units (9) 02/19/2019   M     52,113   (10)   (10) Common Stock 52,113 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
Meaney William L
C/O IRON MOUNTAIN INCORPORATED
ONE FEDERAL STREET
BOSTON, MA 02110		   X     President and CEO  

Signatures

 /s/ Elizabeth Tammaro, under Power of Attorney dated May 26, 2016, from William Meaney   02/21/2019
**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) This acquisition is reported to reflect the partial vesting of restricted stock units ("RSUs") previously granted to the Reporting Person on February 18, 2016.
(2) This acquisition is reported to reflect the partial vesting of RSUs previously granted to the Reporting Person on February 16, 2017.
(3) This acquisition is reported to reflect the full vesting of performance units ("PUs") previously granted to the Reporting Person on February 18, 2016. Effective February 14, 2019, the Compensation Committee of Iron Mountain Incorporated's Board of Directors (the "Compensation Committee") determined the actual award of PUs under the grant after completion of the relevant performance period, and the PUs vested in full on February 18, 2019.
(4) This transaction was effected pursuant to a 10b5-1 trading plan which was approved and became effective as of May 3, 2018.
(5) The price reported in Column 4 is a weighted average price. These shares of Iron Mountain Incorporated common stock ("Common Stock") were sold in multiple transactions at prices ranging from $35.17 to $35.39, inclusive. The Reporting Person undertakes to provide Iron Mountain Incorporated (the "Company"), any security holder of the Company, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares of Common Stock sold at each separate price within the ranges set forth in this footnote (5).
(6) Each RSU represents a contingent right to receive one share of Common Stock.
(7) The RSUs, representing a contingent right to receive a total of 75,162 shares of Common Stock, were granted to the Reporting Person on February 18, 2016 and have vested in full.
(8) The RSUs, representing a contingent right to receive a total of 54,729 shares of Common Stock, were granted to the Reporting Person on February 16, 2017 and vest in three substantially equal annual installments beginning on the first anniversary of the grant date.
(9) Each PU represents a contingent right to receive one share of Common Stock.
(10) The PUs were initially granted to the Reporting Person on February 18, 2016. Effective February 14, 2019, the Compensation Committee determined the actual award of PUs under the grant after completion of the relevant performance period, and the PUs vested in full on February 18, 2019.

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