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 *
DAUTEN KENT P
   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
_____ Officer (give title below) _____ Other (specify below)
(Last)
(First)
(Middle)
KEYSTONE CAPITAL, INC., 520 LAKE COOK ROAD, STE 650		 3. Date of Earliest Transaction (Month/Day/Year)
05/08/2008
(Street)

DEERFIELD, IL 60015		 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 05/08/2008   M   16,416 A $ 12.1837 2,616,416 D  
Common Stock, par value, $.01 per share 05/08/2008   M   9,295 A $ 10.7593 2,625,711 D  
Common Stock, par value, $.01 per share 05/08/2008   M   12,432 A $ 8.0494 2,638,143 D  
Common Stock, par value, $.01 per share 05/08/2008   M   10,195 A $ 19.6178 2,648,338 D  
Common Stock, par value, $.01 per share 05/08/2008   M   7,923 A $ 24.6033 2,656,261 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
Stock Option (right to buy) $ 12.1837 05/08/2008   M     16,416   (1) 05/31/2011 Common Stock 16,416 $ 0 0 D  
Stock Option (right to buy) $ 10.7593 05/08/2008   M     9,295   (2) 05/31/2010 Common Stock 9,295 $ 0 0 D  
Stock Option (right to buy) $ 8.0494 05/08/2008   M     12,432   (3) 05/27/2008 Common Stock 12,432 $ 0 0 D  
Stock Option (right to buy) $ 19.6178 05/08/2008   M     10,195   (4) 05/26/2014 Common Stock 10,195 $ 0 0 D  
Stock Option (right to buy) $ 24.6033 05/08/2008   M     7,923   (5) 05/24/2016 Common Stock 7,923 $ 0 0 D  

Reporting Owners

Reporting Owner Name / Address Relationships
 Director  10% Owner  Officer  Other
DAUTEN KENT P
KEYSTONE CAPITAL, INC.
520 LAKE COOK ROAD, STE 650
DEERFIELD, IL 60015		   X      

Signatures

 /s/ Garry B. Watzke, under Power of Attorney dated September 9, 2002 from Kent P. Dauten   05/12/2008
**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) These options vested from 2001 through 2004.
(2) These options vested from 2000 through 2001.
(3) These options vested from 1998 through 2001.
(4) These options vested from 2004 through 2007.
(5) These options vested on May 25, 2007.

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