<Page>


                             UNCONDITIONAL GUARANTY

                            dated as of May 22, 2001

                                      from

                           IRON MOUNTAIN INCORPORATED
                                  as Guarantor

                                       to

                      IRON MOUNTAIN STATUTORY TRUST - 2001
                                    as Lessor

<Page>

<Table>
                                                                           
1.   Guaranty .................................................................1

2.   Guaranty Continuing and Unlimited.........................................2

3.   Waivers...................................................................3

4.   Subrogation...............................................................4

5.   No Discharge; Reinstatement...............................................5

6.   Events of Default.........................................................5

7.   Assumption of Agreements..................................................6

8.   Obligations Primary.......................................................7

9.   Amendments, Etc...........................................................7

10.  Delivery of Information...................................................7

11.  Covenants.................................................................8

12.  Inspection...............................................................10

13.  Representations and Warranties...........................................10

14.  Third Party Beneficiary..................................................12

15.  Consent to Operative Documents...........................................13

16.  Survival.................................................................13

17.  Successors...............................................................13

18.  Governing Law; Jurisdiction, Etc.........................................13

19.  Severability.............................................................14

20.  Notice...................................................................14

21.  Confidentiality..........................................................14

22.  WAIVER OF JURY TRIAL.....................................................14
</Table>

                                       i
<Page>

                             UNCONDITIONAL GUARANTY

                  THIS UNCONDITIONAL GUARANTY (this "GUARANTY"), dated as of May
22, 2001, from IRON MOUNTAIN INCORPORATED, a Pennsylvania corporation (the
"GUARANTOR"), to IRON MOUNTAIN STATUTORY TRUST - 2001, a Connecticut statutory
trust (the "LESSOR").

                              W I T N E S S E T H:
                              - - - - - - - - - -

                  WHEREAS, the Guarantor wishes to induce the Lessor to enter
into (i) a certain Master Lease and Security Agreement (the "LEASE") dated as of
the date hereof with Iron Mountain Records Management, Inc., a wholly-owned
subsidiary of the Guarantor (the "LESSEE"), (ii) a certain Master Construction
Agency Agreement (the "CONSTRUCTION AGENCY AGREEMENT") dated as of the date
hereof with the Lessee and (iii) certain other Operative Documents (as defined
in the Lease) with the Lessee on or after the date hereof (the Lease, the
Construction Agency Agreement and such other Operative Documents are
collectively referred to hereinafter as the "GUARANTEED AGREEMENTS"); and

                  WHEREAS, the Lessor is unwilling to enter into the Guaranteed
Agreements with the Lessee unless the Guarantor enters into this Guaranty; and

                  WHEREAS, capitalized terms used but not otherwise defined in
this Guaranty have the respective meanings specified in APPENDIX I of the Lease;
and the rules of interpretation set forth in APPENDIX I of the Lease shall apply
to this Guaranty;

                  NOW, THEREFORE, in order to induce the Lessor to enter into
the Guaranteed Agreements and to consummate the transactions contemplated
thereby, the Guarantor hereby agrees as follows:

                  1.      GUARANTY. Guarantor unconditionally and irrevocably
guarantees to (a) the Lessor and (b) to the extent of Lessee's obligations to
the Indemnitees, the Indemnitees, the prompt payment and performance of all
obligations of Lessee under the Guaranteed Agreements (all of the foregoing
obligations and undertakings are collectively referred to hereinafter as the
"GUARANTEED OBLIGATIONS"). This Guaranty is an irrevocable, absolute, present,
primary, continuing, unlimited and unconditional promise with respect to the
full and punctual payment and performance by Lessee of each of the Guaranteed
Obligations, and is not a promise of collectibility only, and is in no way
conditional upon the requirement that Lessor first attempt to collect payment or
demand performance from Lessee or that Lessor resort to any security or other
means of obtaining such payment or performance or upon any other contingency. If
for any reason (i) any such sums shall not be paid promptly by Lessee when due
or (ii) any such covenant, agreement, term or condition is not performed or
observed by Lessee in accordance with any Guaranteed Agreement, Guarantor shall,
without notice or demand of any nature, pay the same by wire transfer of
immediately available federal funds to the Person or Persons entitled thereto
pursuant to the provisions of said instruments and shall perform and observe or
cause to be promptly performed and observed every such covenant, agreement, term
and condition, in each case regardless of (i) any defenses or rights of set-off
or counterclaims which Guarantor or Lessee may have or assert (other than a
defense of payment), (ii) whether Lessor shall have taken any steps to enforce
any rights against Lessee or any other remedy thereunder as a result of the
default of Lessee thereunder and (iii) any other event, condition, contingency
or circumstance whatsoever. Guarantor also agrees to pay to such Persons such
further amounts as shall be sufficient to cover the costs and expenses of
collecting such sums or any part thereof, or of otherwise enforcing or
protecting the rights of such Persons under the Guaranteed Agreements and this
Guaranty, including reasonable fees and expenses of its attorneys and to Lessor
and its attorneys for all services rendered in that connection and in any
related proceeding.

<Page>

                  2.      GUARANTY CONTINUING AND UNLIMITED. The obligations,
covenants, agreements and duties of Guarantor under this Guaranty shall be
absolute and unconditional, shall not be subject to any counterclaim, setoff,
deduction, diminution, abatement, recoupment, suspension, deferment, reduction
or defense based upon any claim that Guarantor or any other Person may have
against Lessee, Lessor or any other Person and, until the payment or performance
in full of the Guaranteed Obligations, shall remain in full force and effect
without regard to, and shall not be released, discharged or in any way affected
by, any circumstance or condition whatsoever (whether or not Lessor, Guarantor
or Lessee shall have any knowledge or notice thereof), including, without
limitation, the happening from time to time of any of the following, although
without notice to, or the consent of, Guarantor:

                  (a)     the waiver by Lessor of the performance or observance
         by  Lessee, Guarantor or any other party of any of the agreements,
         covenants, terms or conditions contained in any Guaranteed Agreement or
         any other instrument or Operative Document;

                  (b)     the extension, in whole or in part, of the time for
         payment by Lessee or Guarantor of any sums owing or payable under any
         Guaranteed Agreement or this Guaranty, as applicable, or of any other
         sums of or obligations under or arising out of or on account of any
         Guaranteed Agreement or the renewal or extension of either thereof;

                  (c)     any assignment or subsequent  reassignment of any
         Guaranteed  Agreementor this Guaranty, in whole or in part, or the
         leasingor subletting of any Property or any part thereof;

                  (d)     the  modification  or amendment  (whether  material or
         otherwise)  of any of the  obligations  of Lessee or Guarantor under
         any Guaranteed Agreement or any other Operative Document,as applicable;

                  (e)     the taking or the omission of any of the acts referred
         to in any Guaranteed Agreement, this Guaranty or any other Operative
         Document (including, without limitation, the giving of any consent
         referred to herein or therein, but excepting therefrom those acts and
         omissions permitted in compliance with and pursuant to the terms of the
         Guaranteed Agreements or this Guaranty, as appropriate);

                  (f)     any failure, omission or delay on the part of Lessor
         to enforce, assert or exercise any right, power or remedy conferred on
         or available to Lessor in or by any Guaranteed Agreement, this Guaranty
         or any other instrument, or any action on the part of Lessor granting
         indulgence or extension in any form whatsoever;

                  (g)     the voluntary or involuntary liquidation, dissolution,
         sale of all or substantially all of the assets, marshaling of assets
         and liabilities, receivership, conservatorship, insolvency, bankruptcy,
         assignment for the benefit of creditors, reorganization, arrangement,
         composition or readjustment of, or other similar proceeding affecting,
         Lessor, Lessee or Guarantor or any of their respective assets;

                  (h)     the release of Lessee or Guarantor from the
         performance or observance of any of the agreements, covenants, terms or
         conditions contained in any Guaranteed Agreement or any other Operative
         Document, as applicable, by operation of law or otherwise, except for
         those releases given or made in compliance with and pursuant to the
         terms of the Guaranteed Agreements or this Guaranty, as applicable, or
         any invalidity or unenforceability of any Guaranteed Agreement or any
         other Operative Document;

                                       2
<Page>

                  (i)     any defect in the title, or any damage to or loss or
         destruction of, or any interruption or cessation in the use of any
         Property or any portion thereof by Lessee for any reason whatsoever
         regardless of the duration thereof (even though such duration would
         otherwise constitute a frustration of any Guaranteed Agreement or this
         Guaranty), whether or not resulting from accident and whether or not
         without fault on the part of Lessee or any other Person;

                  (j)     the inability of Lessor or Lessee to enforce any
         provision of any Guaranteed Agreement for any reason;

                  (k)     any merger or  consolidation  of Lessee or  Guarantor
         into or with any other  Person or any sale, lease or transfer of any of
         the assets of Lessee or Guarantor to any other Person;

                  (l)     any change in the name or corporate ownership of
         Guarantor, Lessee or any other Person referred to herein;

                  (m)     the acceptance or release by Lessor of any other
         security or guarantor for any obligation hereunder;

                  (n)     any value, estimation, termination, rejection,
         discharge or disaffirmance by any Person (including trustees, trustees
         in bankruptcy, liquidators or representatives) of the Guaranteed
         Obligations in connection with any insolvency, bankruptcy,
         reorganization or liquidation of Lessee or any proceeding relating
         thereto;

                  (o)     any determination or claim that Lessor's claims
         against Lessee are or may be limited by Section 502(b) (6) of the
         Bankruptcy Code, as amended, or to any similar or successor provision
         of law upon any rejection of any Guaranteed Agreement in a bankruptcy
         proceeding filed by or against Lessee;

                  (p)     any  failure  or  recharacterization  of title with
         respect to  Lessor's, Lessee's or any other Person's interest in any
         Property; or

                  (q)     any other occurrence or circumstance whatsoever,
         whether similar or dissimilar to the foregoing and any other
         circumstance that might otherwise constitute a legal or equitable
         defense or discharge of the liabilities of a guarantor or surety or
         that might otherwise limit recourse against Guarantor.

                  The obligations of Guarantor set forth herein constitute the
full recourse obligations of Guarantor enforceable against Guarantor to the full
extent of all its assets and properties. In no event shall the obligations of
Guarantor hereunder be subordinated in any manner to any other full recourse
obligations of Guarantor.

                  3.      WAIVERS.

                  (a)     Guarantor unconditionally waives (i) notice of any of
the matters referred to in SECTION 2, (ii) all notices that may be required by
statute, rule of law or otherwise, now or hereafter in effect, to preserve
intact any rights against Guarantor, including, without limitation, any demand,
presentment and protest, proof of notice of non-payment under any Guaranteed
Agreement and notice of Default or Event of Default under any Guaranteed
Agreement or this Guaranty, or any failure on the part of Lessee to perform and
comply with any covenant, agreement, term or condition of any Guaranteed
Agreement, (iii) any right to the enforcement, assertion or exercise against
Lessee of any right, power, privilege or remedy conferred in any Guaranteed
Agreement or otherwise, (iv) any requirement of

                                       3
<Page>

     diligence on the part of Lessor or any other Person, (v) any requirement
that Lessor take any steps to enforce any rights against Lessee under any
Guaranteed Agreement or any other remedy thereunder or any other requirement to
exhaust any remedies or to mitigate the damages resulting from any Default or
Event of Default under any Guaranteed Agreement or this Guaranty, (vi) any
notice of any sale, transfer or other disposition of any right, title to or
interest in any Guaranteed Agreement or any Property covered thereby by Lessor,
(vii) all rights of Guarantor under the laws of the states in which the Property
is located, as the same may be amended, (viii) the occurrence of every other
condition precedent to which the Guarantor or the Lessee may otherwise be
entitled, (ix) the right to have the property of the Lessee first applied to the
discharge of the Guaranteed Obligations; (x) any defense arising by reason of
any disability or other defense of the Lessee or by reason of the cessation from
any cause whatsoever of the liability, either in whole or in part, of the Lessee
to the Lessor for the Guaranteed Obligations, PROVIDED that nothing contained
herein shall be deemed to be a waiver by the Guarantor of the benefit to the
Guarantor of any notice or grace period to which the Lessee is entitled pursuant
to the express terms of the Operative Documents, and (xi) any other circumstance
whatsoever that might otherwise constitute a legal or equitable discharge,
release or defense of a guarantor or surety, or that might otherwise limit
recourse against Guarantor hereunder.

                  (b)     The Lessor may, at its election, exercise any right
 or remedy it may have against the Lessee or any security held by the Lessor,
including, without limitation, the right to foreclose upon any such security by
judicial or nonjudicial sale, without affecting or impairing in any way the
liability of the Guarantor hereunder, except to the extent the Guaranteed
Obligations have been paid, and the Guarantor waives any defense arising out of
the absence, impairment or loss of any right of reimbursement, contribution or
subrogation or any other right or remedy of the Guarantor against the Lessee or
any such security, whether resulting from such election by the Lessor or
otherwise. The Guarantor understands that the liability of the Lessee to the
Lessor for the Guaranteed Obligations may be secured by real property and that
the Guarantor shall be liable for the full amount of its liability hereunder
notwithstanding foreclosure on such real property by trustee sale or any other
reason impairing the Guarantor's right to proceed against the Lessee.
Accordingly, the Guarantor waives, to the fullest extent permitted by applicable
law, all rights and defenses that the Guarantor may have because the Guaranteed
Obligations are secured by real property. This means, among other things, if the
Lessor forecloses on any real property collateral pledged by the Lessee; (x) the
amount of the debt may be reduced only by the price for which the collateral is
sold at the foreclosure sale, even if the collateral is worth more than the sale
price, and (y) the Lessor may collect from the Guarantor even if the Lessor, by
foreclosing on the real property collateral, has destroyed any right the
Guarantor may have to collect from the Lessee. This is an unconditional and
irrevocable waiver, to the fullest extent permitted by applicable law, of any
rights and defenses the Guarantor may have because the Guaranteed Obligations
are secured by real property. These rights and defenses include, but are not
limited to, any rights or defenses based upon Section 580a, 580b, 580d or 726 of
the California Code of Civil Procedure.

                  (c)     The Guarantor assumes the responsibility for being
and keeping informed of the financial condition of the Lessee and of all other
circumstances bearing upon the risk of nonpayment of the Guaranteed Obligations
and agrees that the Lessor shall not have any duty to advise the Guarantor of
information regarding any condition or circumstance or any change in such
condition or circumstance. The Guarantor acknowledges that the Lessor has not
made any representation to the Guarantor concerning the financial condition of
the Lessee.

                  4.      SUBROGATION. Notwithstanding any payment or payments
made or obligation performed by Guarantor by reason of this Guaranty, Guarantor
hereby waives (i) any claim, right or remedy that Guarantor may now or hereafter
acquire against Lessee that arises hereunder and/or by reason of any one or more
payments or acts of performance by Guarantor hereunder, including without
limitation, any claim, remedy or right of subrogation, reimbursement,
exoneration, contribution,

                                       4
<Page>

     indemnification or participation in any claim, right or remedy of the
Lessor against Lessee or any security that Lessor now has or hereafter acquires,
whether or not such claim, right or remedy arises in equity, under contract, by
statute, under common law or otherwise, (ii) any right to enforce any remedy
which Lessee or any other guarantor of Lessee's obligations now has or may
hereafter have against Lessor, and (iii) any right to enforce or exercise the
benefit of and any right to participate in, any security now or hereafter held
by Lessor, in each case until all of the obligations guaranteed hereby are paid
and performed in full. If any amount shall nevertheless be paid to Guarantor by
any such Person in violation of this Guaranty, such amount shall be held by
Guarantor in trust for the benefit of Lessor and shall forthwith be paid to
Lessor. Guarantor further waives any defense to the recovery by Lessor from
Guarantor of any deficiency or otherwise to the enforcement of this Guaranty
after a judicial or nonjudicial sale or other disposition of any security for or
any of the obligations of Lessee under any Guaranteed Agreement, even though
such a sale may prevent Guarantor from exercising rights of subrogation, if any,
contribution or reimbursement against Lessee or any other party. No payment
hereunder by Guarantor shall give rise to any claim by Guarantor against Lessor,
except for payments made in error by Guarantor to the extent such payments are
in excess of amounts due hereunder. Unless and until all obligations of Lessee
under and pursuant to any Guaranteed Agreement, and of Guarantor hereunder,
shall have been discharged by payment or performance in full, Guarantor shall
not assign or otherwise transfer any such claim against Lessee to any other
Person.

                  5.      NO DISCHARGE; REINSTATEMENT. In case any of the
Guaranteed Agreements shall be terminated as a result of the rejection
thereof by any trustee, receiver or liquidating agent of the Lessee or any of
its properties in any bankruptcy, insolvency, reorganization, arrangement,
composition, readjustment, liquidation, dissolution or similar proceeding, the
Guarantor's obligations hereunder shall continue to the same extent as if such
agreement had not been so rejected. The Guarantor agrees that this Guaranty
shall continue to be effective or be reinstated, as the case may be, if at any
time payment or performance to the Lessor of the Guaranteed Obligations or any
part thereof is rescinded or must otherwise be returned by the Lessor upon the
insolvency, bankruptcy or reorganization of the Lessee, or otherwise, as though
such payment to the Lessor had not been made.

                  6.      EVENTS OF DEFAULT. The following events shall
constitute  Events of Default under this Guaranty:

                          (i)   Guarantor shall fail to make any payment due
         hereunder upon demand; or

                          (ii)  (a) there shall occur a breach of any of the
         covenants contained in SECTION 11 (other than those covenants
         incorporated by reference from the Iron Mountain Credit Agreement
         pursuant to SECTION 11(a)(v), except to the extent that a violation of
         any such covenant gives rise to an event of default under the Iron
         Mountain Credit Agreement); or (b) Guarantor shall fail to perform or
         observe any other provision hereof and such failure shall continue for
         25 days after written notice thereof to Guarantor from Lessor; or

                          (iii) if any representation or warranty made by
         Guarantor herein or in any document, certificate or notice furnished by
         Guarantor to Lessor in connection herewith or pursuant hereto shall
         prove to be false or misleading as of the time when made in any
         material respect; or

                          (iv)  (a)if Guarantor shall commence a voluntary case
         under any Bankruptcy Law or file a petition in bankruptcy or for
         reorganization or for an arrangement pursuant to any Bankruptcy Law;
         (b) if Guarantor shall file an order of relief or be adjudicated a
         debtor or a bankrupt under any Bankruptcy Law or become insolvent; (c)
         if Guarantor shall generally not pay

                                       5
<Page>

         its debts as such debts become due or shall make an assignment for the
         benefit of creditors or shall admit in writing its inability to pay its
         debts generally as they become due; or (d) if an involuntary case
         against Guarantor as debtor is commenced by a petition for
         reorganization or liquidation under any Bankruptcy Law, or if a
         petition or answer proposing the adjudication of Guarantor as a
         bankrupt or its reorganization pursuant to any Bankruptcy Law shall be
         filed in any court and Guarantor shall consent to or acquiesce in the
         filing thereof or such case, petition or answer shall not be dismissed,
         discharged or denied within 60 days after filing thereof; or

                          (v)   if a custodian for purposes of any Bankruptcy
         Law of substantially all Guarantor's assets is appointed or otherwise
         takes possession thereof and such appointment remains in effect for
         more than 60 days; or

                          (vi)  if a receiver, U.S. trustee, trustee or
         liquidator of Guarantor or all or substantially all of the assets of
         Guarantor shall be appointed in any proceeding brought by Guarantor, or
         if any such receiver, U.S. trustee, trustee or liquidator shall be
         appointed in any proceeding brought against Guarantor and shall not be
         discharged within 60 days after such appointment, or if Guarantor shall
         consent to or acquiesce in such appointment; or

                          (vii) if there is an Event of Default under any
         Guaranteed Agreement;

then, in each such case, so long as the same shall be continuing, Lessor may, at
its option, declare this Guaranty in default, and at any time thereafter, so
long as Guarantor shall not have remedied all outstanding Events of Default
hereunder, Lessor shall be entitled to exercise any remedy available to it at
law or in equity. No express or implied waiver by Lessor of an Event of Default
hereunder shall in any way be, or be construed to be, a waiver of any further or
subsequent Event of Default. Guarantor hereby waives any right now or
hereinafter conferred upon it by statute or otherwise which may limit or modify
any of Lessor's rights and remedies contained herein. Guarantor agrees to give
written notice to Lessor (a) of any Event of Default hereunder promptly after
the occurrence thereof and (b) of any Event of Default hereunder or under any
Guaranteed Agreement, immediately after the President or Chief Financial Officer
of Guarantor obtains knowledge of the occurrence thereof.

                  7.      ASSUMPTION OF AGREEMENTS.

                  (a)     In the event of a Default or Event of Default under
the Construction Agency Agreement, Guarantor may, and in the event of the
rejection or disaffirmation of the Construction Agency Agreement by Lessee as
debtor in possession or Lessee's trustee in bankruptcy pursuant to any
Bankruptcy Law, Guarantor shall and does hereby (without the necessity of any
further agreement or act), assume all obligations and liabilities of Lessee
under the Construction Agency Agreement to the same extent as if it had been
originally named instead of such Lessee as a party to such documents and there
had been no such rejection or disaffirmance; and Guarantor shall confirm such
assumption in writing at the request of Lessor upon or after such rejection or
disaffirmance. Guarantor, upon such assumption, will have all rights of Lessee
under the Construction Agency Agreement. From and after the date of such
assumption, as provided in this SECTION 7(a), all provisions of this Guaranty
shall continue in full force and effect as separate and independent undertakings
of Guarantor, binding upon and enforceable against Guarantor without regard to
the validity or enforceability of such assumption, and all provisions of this
Guaranty applicable to the Construction Agency Agreement and to Lessor and
Lessee in respect of the Construction Agency Agreement shall also apply to such
assumption and to Lessor and Guarantor in respect of such assumption to the same
extent and in the same manner as such provisions are applicable to the
Construction Agency Agreement and to Lessor and Lessee in respect of the
Construction Agency Agreement.

                                       6
<Page>

                  (b)     In the event of a Default or Event of Default under
the Lease, Guarantor may, and in the event of the rejection or disaffirmation of
the Lease by Lessee as debtor in possession or Lessee's trustee in bankruptcy
pursuant to any Bankruptcy Law, Guarantor shall and does hereby (without the
necessity of any further agreement or act), assume all obligations and
liabilities of Lessee under the Lease to the same extent as if it had been
originally named instead of such Lessee as a party to such documents and there
had been no such rejection or disaffirmance; and Guarantor shall confirm such
assumption in writing at the request of Lessor upon or after such rejection or
disaffirmance. Guarantor, upon such assumption, will have all rights of Lessee
under the Lease. From and after the date of such assumption, as provided in this
SECTION 7(b), all provisions of this Guaranty shall continue in full force and
effect as separate and independent undertakings of Guarantor, binding upon and
enforceable against Guarantor without regard to the validity or enforceability
of such assumption, and all provisions of this Guaranty applicable to the Lease
and to Lessor and Lessee in respect of the Lease shall also apply to such
assumption and to Lessor and Guarantor in respect of such assumption to the same
extent and in the same manner as such provisions are applicable to the Lease and
to Lessor and Lessee in respect of the Lease.

                  8.      OBLIGATIONS  PRIMARY.  It is agreed that the
liabilities and obligations of Guarantor hereunder are primary and those of a
principal,  and are enforceable  either before,  simultaneously  with or after
proceeding  against  Lessee or against any  property or  security  available  to
Lessor.

                  9.      AMENDMENTS, ETC. This Guaranty may not be modified or
amended  except by a written  agreement duly executed by Guarantor with the
consent  in  writing  of  Lessor  and the  Administrative  Agent.  Neither  this
Guaranty, nor any of the obligations of Guarantor hereunder,  may be assigned to
any Person by Guarantor.

                  10.     DELIVERY OF INFORMATION.  Guarantor shall furnish the
following financial  information to the Lessor, each Equity Participant and the
Administrative  Agent  (and the  Administrative  Agent  will  deliver  such
materials to each Lender):

                  (a)     as soon as practicable, copies of all such financial
statements, proxy statements, notices, other communications and reports as
Guarantor shall send on a regular basis to its shareholders and other
information, if any, generally made available to banks and other lenders
(exclusive of proprietary information);

                  (b)     for any period that Guarantor is a public company,
copies of all reports on Form 10-K and Form 10-Q (and any  successor  form) in
each  case  together  with a list  describing  all  reports  filed  with  the
Securities and Exchange  Commission  during the reporting  period,  and any such
listed  reports  shall be delivered to the  Administrative  Agent and any Lender
upon such Lender's  request  which  Guarantor is or may be required to file with
the  Securities  and  Exchange  Commission  or any  governmental  body or agency
succeeding to the functions of the Securities and Exchange Commission;

                  (c)     for any period that Guarantor is not a public company
required to file such reports with the Securities and Exchange Commission, then
within 105 days after the end of each fiscal year, and within 60 days after the
end of any other fiscal quarter, financial statements containing substantially
the same information as the information that would be included in such reports
on Form 10-K or Form 10-Q, as the case may be, and in any event, all in
reasonable detail and satisfactory in scope to the Administrative Agent, the
Lessor and the Lessor's mortgagee, all prepared in accordance with GAAP and,
with respect to the annual statements, audited, by independent certified public
accountants of recognized national standing selected by Guarantor; and

                  (d)     within 30 days after the beginning of each fiscal
year of the  Guarantor  commencing  with  fiscal  year 2002,  a copy of the
consolidated operating budget, including, without

                                     7
<Page>
limitation,  projection of the anticipated  cash flow, of the Guarantor and its
Subsidiaries  for such  fiscal  year,  such budget to be  accompanied  by a
certificate of the Chief Financial  Officer or Vice  President-Treasurer  of the
Guarantor specifying the assumptions on which such budget was prepared,  stating
that such officer has no reason to question the  reasonableness  of any material
assumptions  on which such budget was prepared and providing  such other details
as the Administrative Agent may reasonably request.

Concurrently with the delivery of quarterly financial statements pursuant
hereto, Guarantor shall cause to be delivered to the Lessor, each Equity
Participant and the Administrative Agent (and the Administrative Agent will
deliver such materials to each Lender) an Officer's Certificate (i) stating that
to the best of the knowledge of the Chief Executive Officer, Chief Financial
Officer or Vice President-Treasurer executing such Officer's Certificate based
on reasonable inquiry, there exists no Default or Event of Default under the
Lease, the Construction Agency Agreement or this Guaranty or if any such Default
or Event of Default exists, specifying the nature thereof, the period of
existence thereof and what action Guarantor proposes to take with respect
thereto and (ii) setting forth such information as shall be necessary for the
Lessor, each Equity Participant and the Administrative Agent to confirm
compliance by Guarantor with the covenants contained in SECTION 11 hereof.

                  11.     COVENANTS.

                  (a)     Guarantor hereby covenants and agrees as follows:

                          (i)   LEVERAGE RATIO. The Guarantor will not, as at
         the end of any fiscal quarter, permit the ratio, calculated as at the
         end of such fiscal quarter for the period of four fiscal quarters then
         ended, of (i) the excess of (x) the aggregate outstanding principal
         amount of Funded Indebtedness (on a consolidated basis) of the
         Guarantor and its Subsidiaries at such date OVER (y) the aggregate
         amount of cash and Liquid Investments of the Guarantor and its
         Subsidiaries at such date to (ii) Consolidated EBITDA for such period
         (the "LEVERAGE RATIO") to exceed the ratio set forth below:

<Table>
<Caption>
         -----------------------------------------------------------------------
         PERIOD                                                LEVERAGE RATIO
         -----------------------------------------------------------------------
                                                              
         From the Effective Date through June 30,                5.75 to 1
         -----------------------------------------------------------------------
         From July 1, 2001 through June 30, 2002                 5.50 to 1
         -----------------------------------------------------------------------
         From July 1, 2002 through June 30, 2003                 5.25 to 1
         -----------------------------------------------------------------------
         From July 1, 2003 and at all times thereaf              5.00 to 1
         -----------------------------------------------------------------------
</Table>
                          (ii)  INTEREST COVERAGE RATIO. Guarantor will not, as
         at the end of any fiscal quarter, permit the ratio, calculated as at
         the end of such fiscal quarter for the period of four fiscal quarters
         then ended, of (i) Consolidated EBITDA for such period to (ii) Interest
         Expense for such period to be less than the ratio set forth below for
         the period in which such fiscal quarter ends:
<Table>
<Caption>
         -----------------------------------------------------------------------
                                                                INTEREST
         PERIOD                                               COVERAGE RATIO
         -----------------------------------------------------------------------
                                                              
         From the Effective Date through June 30, 2001           1.75 to 1
         -----------------------------------------------------------------------
         From July 1, 2001 through December 31, 2002             2.00 to 1
         -----------------------------------------------------------------------
         From January 1, 2003 through December 31, 2003          2.25 to 1
         -----------------------------------------------------------------------
         From January 1, 2004 and at all times thereafter        2.50 to 1
         -----------------------------------------------------------------------
</Table>
                          For purposes of calculating any ratio set forth in
         this subsection (ii), if Guarantor elects pursuant to the penultimate
         sentence of the definition of Consolidated EBITDA to include in
         Consolidated EBITDA for the period to which such ratio relates the PRO
         FORMA amounts
                                       8
<Page>
         referred to in such sentence, there shall be included in
         Interest Expense for such period, on a PRO FORMA basis, interest
         accruing during such period on Indebtedness (and the interest portion
         of payments under Capitalized Lease Obligations) assumed or incurred by
         Guarantor and its Subsidiaries (on a consolidated basis) in connection
         with any Permitted Acquisition having Acquisition Consideration of more
         than $500,000 during such period.

                          (iii) FIXED CHARGES COVERAGE RATIO. Guarantor will
         not, as at the end of any fiscal quarter, permit the ratio, calculated
         as at the end of such fiscal quarter for the period of four fiscal
         quarters then ended, of (i) Adjusted EBITDA for such period to (ii)
         Fixed Charges for such period to be less than the ratio set forth below
         for the period in which such fiscal quarter ends:
<Table>
<Caption>
         -----------------------------------------------------------------------
                                                              FIXED CHARGES
         PERIOD                                               COVERAGE RATIO
         -----------------------------------------------------------------------
                                                              
         From the Effective Date through June 30, 2001           1.00 to 1
         -----------------------------------------------------------------------
         From July 1, 2001 through June 30, 2003                 1.10 to 1
         -----------------------------------------------------------------------
         From July 1, 2003 and at all times thereafter           1.20 to 1
         -----------------------------------------------------------------------
</Table>
                          For purposes of calculating any ratio set forth in
         this subsection (iii), if Guarantor elects pursuant to the penultimate
         sentence of the definition of Consolidated EBITDA to include in
         Consolidated EBITDA for the period to which such ratio relates the PRO
         FORMA amounts referred to in such sentence, there shall be included in
         Fixed Charges for such period, on a PRO FORMA basis, principal payable
         and interest accruing during such period on Indebtedness (and the
         interest portion of payments under Capitalized Lease Obligations)
         assumed or incurred by Guarantor and its Subsidiaries (on a
         consolidated basis) in connection with any Permitted Acquisition having
         Acquisition Consideration of more than $500,000 during such period.

                          (iv)  LIENS. Guarantor will not, and will not permit
         any of its Subsidiaries to, create or suffer to exist any Lien upon any
         property or assets, now owned or hereafter acquired, securing any
         Indebtedness or other obligation, except: (i) the Liens covering the
         capital stock and equity interests (and proceeds thereof) of any
         Subsidiaries of the Guarantor, securing the obligations of the
         Guarantor under the Iron Mountain Credit Agreement; (ii) the Liens
         existing on the Effective Date set forth in SCHEDULE III of the Iron
         Mountain Credit Agreement (as in effect on the date hereof without
         regard to any subsequent amendment, modification, waiver, supplement or
         termination of such credit agreement) and Liens arising out of the
         refinancing, extension, renewal or refunding of any Indebtedness
         secured by any Lien set forth on such SCHEDULE III, PROVIDED that the
         principal amount of such Indebtedness is not increased and is not
         secured by any additional assets; (iii) (A) Liens contemplated by
         CLAUSES (ii), (iv), (v) and (vii) of the definition of Permitted
         Indebtedness set forth in the Iron Mountain Credit Agreement; and (B)
         Liens securing Acquired Debt, PROVIDED that such Liens cover only those
         assets that were covered by such Liens prior to the relevant
         acquisition; (iv) attachment, judgment or other similar Liens arising
         in connection with litigation or other legal proceedings, PROVIDED that
         either (A) the claims in respect of such Liens are fully covered by
         insurance or (B) the execution or other enforcement of such Liens is
         effectively stayed and the claims secured thereby are in an amount not
         to exceed $3,000,000 in the aggregate and are being contested in good
         faith by appropriate proceedings diligently prosecuted; (v) Liens on
         properties or assets of an Excluded Subsidiary securing Indebtedness of
         such Excluded Subsidiary permitted hereunder; (vi) other Liens arising
         in the ordinary course of the business of the Guarantor or such
         Subsidiary which are not incurred in connection with the borrowing of
         money or the obtaining of advances or credit and which do not
         materially detract from the value of its property or assets or
         materially impair the use thereof in the operation of its business;
         (vii) Liens securing Indebtedness permitted by CLAUSE (v) of SECTION
         9.08 of the Iron Mountain Credit Agreement (as in effect on the date
         hereof without

                                       9
<Page>

         regard to any subsequent amendment, modification, waiver, supplement or
         termination of such credit agreement), PROVIDED that such Liens extend
         only to the assets of any Excluded Subsidiary incurring such
         Indebtedness as a primary obligor (and not as a guarantor) or capital
         stock of such Excluded Subsidiary; (viii) Liens on property leased
         pursuant to the Synthetic Lease Obligations permitted by CLAUSE (vi) of
         SECTION 9.08 of the Iron Mountain Credit Agreement (as in effect on the
         date hereof without regard to any subsequent amendment, modification,
         waiver, supplement or termination of such credit agreement) and (ix)
         Liens under the instruments governing (A) an Accounts Receivable
         Financing or (B) a Mortgage Financing permitted by SECTION 9.08 of the
         Iron Mountain Credit Agreement (as in effect on the date hereof without
         regard to any subsequent amendment, modification, waiver, supplement or
         termination of such credit agreement).

                          (v)   OTHER COVENANTS. Guarantor will comply with all
         covenants of Guarantor contained in SECTION 9 of the Iron Mountain
         Credit Agreement, all of which are incorporated herein by reference;
         provided, however, to the extent that any such covenant is inconsistent
         with any covenant in the Operative Documents, including, without
         limitation contained in this subparagraph (a), such covenant in the
         Operative Documents shall control and shall not be subject to (b)
         below.

                          (vi)  LESSEE'S EBITDA. The Guarantor will not, as at
         the end of any fiscal quarter, permit: (a) the Lessee's Consolidated
         EBITDA, calculated as at the end of such fiscal quarter for the quarter
         then ended, to be less than an amount equal to 70% of the Guarantor's
         Consolidated EBITDA for such period; or (b) Unconsolidated EBITDA,
         calculated as at the end of such fiscal quarter for the quarter then
         ended, to be less than an amount equal to 50% of the Guarantor's
         Consolidated EBITDA for such period.

                  (b)     The covenants incorporated by reference in SECTION
11(a)(v) above, and the related definitions shall, without further action
hereunder, be amended to conform to any amendment, written waiver, or
modification to such covenants (or related definitions) contained in the Iron
Mountain Credit Agreement; PROVIDED, HOWEVER, that if the Iron Mountain Credit
Agreement shall be terminated for any reason, the form of the covenants and the
related definitions incorporated by reference in SECTION (a)(v) above at the
time of such termination shall continue hereunder and Guarantor shall execute
such amendments or supplements hereto evidencing such survival as the
Administrative Agent may reasonably request.

                  12.     INSPECTION. Guarantor will permit the Lessor, each
Equity Participant, the Collateral Agent, the Administrative Agent and each
Lender to visit the offices of  Guarantor at its address set forth herein and to
examine its records  and books of account and to discuss its  affairs,  finances
and accounts with its officers upon reasonable  notice at such reasonable  times
as may be  requested  by the Lessor,  such Equity  Participant,  the  Collateral
Agent, the Administrative Agent or such Lender.

                  13.     REPRESENTATIONS AND WARRANTIES.  Guarantor represents
and warrants that:
                  (a)     Guarantor (i)is a corporation duly organized, validly
existing and in good standing under the laws of the Commonwealth of
Pennsylvania, and (ii) has all requisite legal power and authority to enter into
this Guaranty, to perform and observe the terms and conditions hereof and has
all requisite legal power and authority to own, lease and operate its properties
and conduct its business as currently conducted except for such licenses,
permits and approvals which would not, individually or in the aggregate, have a
material adverse effect on Guarantor's ability to perform the Guaranteed
Obligations. Guarantor is qualified to do business as a foreign corporation in
all jurisdictions where its ownership of property or the nature of its business
requires such qualification. This Guaranty has been duly authorized, executed
and delivered by Guarantor and constitutes the legal, valid and binding

                                       10
<Page>

obligation by Guarantor enforceable against Guarantor in accordance with its
terms, except as enforcement may be limited by bankruptcy, insolvency,
reorganization and other laws of general application relating to or affecting
the enforcement of creditors' rights and general principles of equity.

                  (b)     There are no actions, suits or proceedings pending
or, to its knowledge, threatened against or affecting Guarantor, the Lessee
or any of their Subsidiaries at law or in equity before any court or
administrative officer or agency in which there is a reasonable possibility of
an adverse determination which could, individually or in the aggregate, have a
material adverse effect on Guarantor's ability to perform the Guaranteed
Obligations. Guarantor, the Lessee or any of their Subsidiaries is not in
default (i) in the payment of any taxes levied or assessed against it or its
assets or (ii) under or in violation of any statute, rule, order, decree, writ,
injunction or regulation (including Environmental Laws) of any Governmental
Authority except, where the failure to pay such taxes or the existence of such
defaults or violations would, individually or in the aggregate, not have a
material adverse effect on Guarantor's ability to perform the Guaranteed
Obligations.

                  (c)     Guarantor is not a party to any contract or agreement
or subject to any restriction or to any order, rule, regulation, writ,
injunction or decree of any court or Governmental Authority or to any statue
which materially and adversely affects its ability to perform the Guaranteed
Obligations. Neither the execution, delivery or performance by Guarantor of this
Guaranty nor its compliance herewith or therewith (i) conflicts or will conflict
with or results or will result in a breach of or constitutes or will constitute
a default under (A) any law in effect as of the date of delivery of this
Guaranty, (B) the articles of incorporation or by-laws of Guarantor, (C) any
agreement or instrument to which Guarantor is a party or by which it is bound,
or (D) any order, writ, injunction or decree of any court or other Governmental
Authority, or (ii) results or will result in the creation or imposition of any
Lien, charge or encumbrance upon Guarantor's property pursuant to such agreement
or instrument.

                  (d)     The execution, delivery and performance by Guarantor
of this Guaranty do not require (i) any stockholder approval or the consent or
approval  of any of  Guarantor's  creditors  (except  as have  already  been
obtained in writing), or (ii) any authorization,  consents, or approvals,  of or
filings  with  any  Governmental  Authority,   except  for  such  authorization,
consents,  approvals or filings  which have been  obtained and are in full force
and effect.

                  (e)     No event has occurred and is continuing with respect
to Guarantor which would constitute a Default or an Event of Default hereunder.
No Default or Event of Default by Lessee exists under any Guaranteed Agreement.
Guarantor is not in default in the payment of the principal or interest on any
indebtedness for borrowed money or for its deferred purchase of property or in
default under any instrument or agreement under and subject to which any such
indebtedness has been issued or under any lease, in any case involving the
likelihood of any actions or proceedings against it which would materially and
adversely affect Guarantor or its ability to perform under this Guaranty.

                  (f)     The Guarantor and each member of the Controlled Group
have fulfilled their obligations under the minimum funding standards of ERISA
and the Code with respect to each Plan and are in compliance in all material
respects with the presently applicable provisions of ERISA and the Code, and
have not incurred any liability to the PBGC or a Plan under Title IV of ERISA
(other than to make contributions or premium payments in the ordinary course).

                  (g)     Guarantor's assets are not less than its liabilities,
both  determined in  accordance  with GAAP,  and Guarantor is solvent.  The
transactions  contemplated  by this Guaranty are in  furtherance  of Guarantor's
ordinary business purposes and in furtherance of its corporate purposes with no
contemplation of insolvency and with no intent to hinder, delay or defraud any
of its present or future creditors. Neither before nor as a result of the
 transactions contemplated by this Guaranty will Guarantor

                                       11
<Page>

be or be rendered  insolvent or have an unreasonably  small capital for the
conduct of its business and the payment of its anticipated obligations.
Guarantor's assets and cash flow enable it to meet its present obligations in
the ordinary course of business as they become due, and Guarantor does not
believe that it will incur debts beyond its ability to pay such debts.

                  (h)     The Guarantor has disclosed to the Administrative
Agent in writing any and all facts (other than general economic conditions)
which materially and adversely affect or may materially and adversely affect (to
the extent that it can reasonably foresee) the business, assets, property,
condition (financial or otherwise) or prospects of the Guarantor and its
Subsidiaries taken as a whole, or the ability of the Guarantor and the Lessee to
perform its obligations under each Operative Document to which it is a party.
The information, reports, financial statements, exhibits and schedules furnished
in writing by or on behalf of the Guarantor to the Administrative Agent or any
Lender in connection with the negotiation, preparation or delivery of this
Guaranty and the other Operative Documents or included herein or therein or
delivered pursuant hereto or thereto, when taken as a whole do not contain any
untrue statement of material fact or omit to state any material fact necessary
to make the statements herein or therein, in light of the circumstances under
which they were made, not misleading; PROVIDED, that with respect to any such
information, report, financial statement, exhibit or schedule to the extent that
it was based upon or constitutes a forecast or projection, the Guarantor
represents only that it acted in good faith and utilized reasonable assumptions
and due care in the preparation of such information, report, financial
statement, exhibit or schedule. All written information furnished after the date
hereof by the Guarantor to the Administrative Agent and the Lenders and required
in connection with this Guaranty and the other Operative Documents and the
transactions contemplated hereby and thereby will be true, complete and accurate
in every material respect, or (in the case of projections) based on reasonable
estimates, on the date as of which such information is stated or certified.
Guarantor represents that the consolidated financial statements for the
Guarantor's fiscal year ending on December 31, 2000 specified above (i) are in
accordance with the books and records of the Guarantor and its Subsidiaries,
which have been maintained in accordance with good business practice, (ii)
present fairly in all material respects the financial condition of Guarantor on
the dates for which, and the results of its operations for the periods for
which, the same have been furnished, and (iii) have been prepared in accordance
with GAAP consistently applied, except as otherwise disclosed therein. Guarantor
represents that as of the Closing Date there shall have been no material adverse
change in the condition of the Lessee, financial or otherwise, since the date of
the most recent financial statements of Guarantor delivered to the Lessor.

                  (i)     Neither the Guarantor nor any of its Subsidiaries is
subject to regulation under the Investment Company Act of 1940, the Public
Utility Holding Company Act of 1935, the Federal Power Act, any state public
utilities code or any other law, rule, decree, guideline or policy of any
Governmental Authority that limits its ability to incur Indebtedness.

                  (j)     There has been no material adverse change in
Guarantor's business or financial condition since December 31, 2000 that
individually or the aggregate would adversely affect Guarantor's ability to
perform the Guaranteed Obligations.

                  (k)     At the Effective Date and after giving effect to the
consummation of the transactions contemplated by this Guaranty, the Guarantor
will (i) have capital, cash flows and sources of working capital financing
sufficient to carry on its business and transactions and all business and
transactions in which it is about to engage, (ii) be able to pay its debts as
they mature, and (iii) have assets (tangible and intangible) whose fair salable
value exceeds its total liabilities (including contingent, subordinated,
unmatured and unliquidated liabilities).

                  14.     THIRD PARTY  BENEFICIARY.  The Guarantor  expressly
acknowledges  and agrees that each  Indemnitee (as such term is defined in the
Lease) shall be a third party beneficiary of this Guaranty.

                                       12
<Page>

                  15.     CONSENT TO OPERATIVE DOCUMENTS.  The Guarantor
acknowledges and consents to, and agrees as follows:

                  (a)     The Guarantor has received a copy of each of the
Operative Documents as it has required in connection herewith and agrees that
such a copy constitutes adequate notice of the terms contained therein.

                  (b)     The Guarantor consents to the execution, delivery and
performance of the Security Documents, to the assignment, pledge, transfer and
grant to the Collateral Agent of a continuing security interest in, and a lien
upon, the Collateral (including this Guaranty) in the manner and for the
purposes of the Security Documents, to all of the terms and provisions of the
Security Documents and to the exercise by the Collateral Agent of any right,
remedy, power or privilege granted to the Collateral Agent under the Security
Documents in accordance with the terms thereof as now or at any time hereafter
in effect. The Guarantor further consents to the execution, delivery and
performance of each of the Operative Documents and to the respective terms and
provisions thereof.

                  (c)     The Lessor hereby irrevocably instructs the Guarantor
to pay any and all amounts payable to the Lessor under this Guaranty directly to
the [account specified by the Collateral Agent] until the Lessor has notified
the Guarantor that the Credit Agreement has terminated. The Guarantor hereby
agrees that any payment by it in accordance with such instructions shall be made
free and clear of any setoff, counterclaim or defense whatsoever that the
Guarantor may have with respect thereto; PROVIDED, HOWEVER, that no payment by
the Guarantor to the Collateral Agent shall be deemed a waiver of any rights the
Guarantor may have against the Collateral Agent or any other Person.

                  (d)     By reason of the Intercreditor Agreement, all of the
Guarantor's obligations under this Guaranty, together with all of the rights and
remedies of the Lessor thereunder, shall be enforceable by the Collateral Agent
directly against the Guarantor.

                  (e)     The Collateral Agent may, in realizing upon the
Collateral, assign all or any part of its rights and interest in this Guaranty
to any other Person without the Guarantor's consent.

                  16.     SURVIVAL. All agreements, covenants, representations
and warranties contained herein or made in writing by Guarantor shall survive
the execution and delivery of this Guaranty and shall continue in full force and
effect until all of the obligations of the Guarantor under this Guaranty shall
be fully performed in accordance with the terms hereof, and until the payment in
full of all sums payable by the Lessee under the Guaranteed Agreements, and
until performance in full of all obligations of the Lessee in accordance with
the terms and provisions of such agreements.

                  17.     SUCCESSORS. This Guaranty  shall be binding upon, and
inure to the benefit of, the parties hereto and their respective successors
and assigns.

                  18.     GOVERNING LAW; JURISDICTION, ETC. This Guaranty shall
be construed and enforced in accordance with, and governed by, the laws of the
State of New York. The Guarantor irrevocably submits to the non-exclusive
jurisdiction of the courts of the State of New York and the courts of the United
States of America located in the Southern District of New York and agrees that
any legal action, suit or proceeding arising out of or relating to this Guaranty
or any of the other Operative Documents may be brought against such party in any
such courts. To the extent permitted by law, final judgment against the
Guarantor in any such action, suit or proceeding shall be conclusive and may be
enforced in any other jurisdiction by suit on the judgment, a certified or
exemplified copy of which shall be conclusive evidence of the judgment, or in
any other manner provided by law. Nothing in this SECTION 18 shall affect the
right of Lessor, Collateral Agent or any Lender to commence legal proceedings

                                       13
<Page>

or otherwise sue the Guarantor in any other appropriate jurisdiction, or
concurrently in more than one jurisdiction, or to serve process, pleadings and
other papers upon the Guarantor in any manner authorized by the laws of any such
jurisdiction. The Guarantor agrees that process served either personally or by
registered mail shall, to the extent permitted by law, constitute adequate
service of process in any such suit.

                  19.     SEVERABILITY. Any provision of this Guaranty which is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

                  20.     NOTICE. Any notice, demand or other communication to
be given under this Guaranty shall be given in the manner and with the effect
provided in the Lease and, in the case of the Guarantor, shall be sent to the
address specified below (or such other address as the Guarantor may designate in
writing):

                  Iron Mountain Incorporated
                  745 Atlantic Avenue
                  Boston, MA 02111
                  Attention:  Treasurer
                  Telephone:  (617) 535-4766
                  Telecopier:  (617) 350-7881

                  21.     CONFIDENTIALITY. The Lessor agrees to exercise all
reasonable efforts to keep any information delivered or made available by or on
behalf of the Guarantor or any Subsidiary thereof to it which has not been
publicly disclosed confidential from anyone other than persons employed or
retained by the Lessor who are or are expected to become engaged in evaluating
or administering the transactions contemplated by the Operative Documents;
PROVIDED that nothing herein shall prevent the Lessor from disclosing such
information (i) to the Collateral Agent, the Administrative Agent, any Lender,
any Equity Participant and each of the officers, directors, employees, agents,
attorneys and accountants of such Persons, in each case provided that such
recipient receives such information having been made aware of the restrictions
set forth in this Section, (ii) upon the order of any court or administrative
agency, (iii) upon the request or demand of any regulatory agency or authority
having jurisdiction over the Lessor, (iv) to the extent reasonably required in
connection with any litigation to which the Administrative Agent, the Collateral
Agent, any Lender or any Equity Participant or their respective affiliates may
be a party, (v) to the extent reasonably required in connection with the
exercise of any remedy hereunder, (vi) to such Lessor's legal counsel and
independent auditors and (vii) to any actual or proposed assignee of all or part
of its rights hereunder which has agreed in writing to be bound by the
provisions of this Section 21.

                  22.     WAIVER OF JURY TRIAL. GUARANTOR HEREBY IRREVOCABLY
WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO
TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS
GUARANTY OR THE TRANSACTIONS CONTEMPLATED HEREBY. THIS WAIVER IS KNOWINGLY,
INTENTIONALLY AND VOLUNTARILY MADE BY GUARANTOR; AND GUARANTOR FURTHER
ACKNOWLEDGES THAT IT HAS BEEN REPRESENTED (OR HAS HAD THE OPPORTUNITY TO BE
REPRESENTED) IN THE SIGNING OF THIS GUARANTY AND THE MAKING OF THIS WAIVER BY
INDEPENDENT LEGAL COUNSEL, SELECTED OF ITS OWN FREE WILL, AND THAT IT HAS HAD
THE OPPORTUNITY TO DISCUSS THIS WAIVER WITH COUNSEL.

                                       14
<Page>

                  IN WITNESS WHEREOF, Guarantor has caused this Unconditional
Guaranty to be executed under seal and delivered as of the day and year first
above written.


                                                   IRON MOUNTAIN INCORPORATED


                                                   By: /s/ John P. Lawrence
                                                      -------------------------
                                                      Name:  John P. Lawrence
                                                      Title: Vice President
                                                             and Treasurer


                                       1