<Page>
                                                Filed Pursuant to Rule 424(b)(3)
                                                      Registration No. 333-75068

PROSPECTUS

                                  $500,000,000
                            IRON MOUNTAIN INCORPORATED

               DEBT SECURITIES, PREFERRED STOCK, DEPOSITARY SHARES,
                           COMMON STOCK AND WARRANTS

                                ----------------

We may from time to time offer:

<Table>
    
- -      debt securities;

- -      shares of our preferred stock;

- -      fractional shares of our preferred stock in
       the form of depositary shares;

- -      shares of our common stock;

- -      warrants to purchase any of these
       securities; or

- -      stock purchase contracts.
</Table>

    The securities we offer will have an aggregate public offering price of up
to $500,000,000. These securities may be offered and sold separately or together
in units with other securities described in this prospectus.

    In connection with the debt securities, substantially all of our present and
future wholly owned domestic subsidiaries may, on a joint and several basis,
offer full and unconditional guarantees of our obligations under the debt
securities.

    IM Capital Trust I may, from time to time, offer trust preferred securities
which will be fully and unconditionally guaranteed by us. Our guarantees may be
senior or subordinated. The trust preferred securities may be offered and sold
separately or together in units with other securities described in this
prospectus.

    We and IM Capital Trust I will indicate the particular securities we offer
and their specific terms in a supplement to this prospectus. In each case we
would describe the type and amount of securities we are offering, the initial
public offering price and the other terms of the offering.

    Our common stock is listed on the New York Stock Exchange under the symbol
"IRM." We will make applications to list any shares of common stock sold
pursuant to a supplement to this prospectus on the NYSE. We have not determined
whether we will list any of the other securities we may offer on any exchange or
over-the-counter market. If we decide to seek listing of any securities, the
supplement will disclose the exchange or market.

    INVESTING IN OUR SECURITIES INVOLVES RISKS. SEE "RISK FACTORS" BEGINNING ON
PAGE 2.

    NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY STATE SECURITIES
COMMISSION HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR DETERMINED IF THIS
PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.

    Our and IM Capital Trust I's principal place of business is 745 Atlantic
Avenue, Boston, Massachusetts 02111 and our and IM Capital Trust I's telephone
number is (617) 535-4766.

                 THE DATE OF THIS PROSPECTUS IS FEBRUARY 11, 2002.
<Page>
                               TABLE OF CONTENTS

<Table>
<Caption>
                                                                PAGE
                                                              --------
                                                           
About This Prospectus.......................................     (i)
Cautionary Note Regarding Forward-Looking Statements........    (ii)
Our Company.................................................      1
IM Capital Trust............................................      1
Risk Factors................................................      2
Ratio of Earnings to Fixed Charges..........................      7
Use of Proceeds.............................................      8
Description of Our Debt Securities..........................      8
Description of Our Capital Stock............................     16
Description of Our Depositary Shares........................     18
Description of Our Warrants.................................     21
Description of the Stock Purchase Contracts and the Stock
  Purchase Units............................................     22
Description of the Trust Preferred Securities...............     23
Description of the Trust Preferred Securities Guarantee.....     24
Relationship Among the Debt Securities, the Trust Preferred
  Securities and the Trust Preferred Securities Guarantee...     28
Description of Certain Provisions of Pennsylvania Law and
  Our Articles of Incorporation and Bylaws..................     30
Plan of Distribution........................................     31
Validity of the Offered Securities..........................     32
Experts.....................................................     33
Where You Can Find More Information.........................     33
Documents Incorporated By Reference.........................     33
</Table>

                             ABOUT THIS PROSPECTUS

    This prospectus is part of a registration statement we filed with the
Securities and Exchange Commission, or the SEC, using a "shelf" registration
process. Under this shelf process, we may sell any combination of the securities
described in this prospectus in one or more offerings up to a total dollar
amount of proceeds of $500,000,000 or the equivalent denominated in foreign
currency. This prospectus provides you with a general description of the
securities we may offer. Each time we sell securities, we will provide a
prospectus supplement containing specific information about the terms of that
offering. The prospectus supplement may also add, update, or change information
contained in this prospectus. You should read both this prospectus and any
prospectus supplement, together with additional information described under the
heading "Where You Can Find More Information" and "Documents Incorporated By
Reference."

    We have not included, or incorporated by reference, separate financial
statements of IM Capital Trust I in this prospectus. Neither we nor IM Capital
Trust I consider these financial statements material to holders of the trust
preferred securities because:

    - IM Capital Trust is a special purpose entity;

    - IM Capital Trust does not have any operating history or independent
      operations; and

    - IM Capital Trust is not engaged in, nor will it engage in, any activity
      other than issuing trust preferred and trust common securities, investing
      in and holding our debt securities and engaging in related activities.

                                      (i)
<Page>
    Furthermore, the combination of our obligations under our debt securities,
the associated indentures, IM Capital Trust's declaration of trust and our
related guarantees provide a full and unconditional guarantee of payments of
distributions and other amounts due on the trust preferred securities. In
addition, we do not expect that IM Capital Trust will file reports with the SEC
under the Securities Exchange Act of 1934, as amended.

    YOU SHOULD RELY ONLY ON THE INFORMATION INCORPORATED BY REFERENCE OR
PROVIDED IN THIS DOCUMENT AND ANY PROSPECTUS SUPPLEMENT. NEITHER WE NOR IM
CAPITAL TRUST HAVE AUTHORIZED ANYONE ELSE TO PROVIDE YOU WITH DIFFERENT
INFORMATION. NEITHER WE NOR IM CAPITAL TRUST ARE MAKING AN OFFER OF THESE
SECURITIES IN ANY JURISDICTION WHERE IT IS UNLAWFUL. IF ANYONE PROVIDES YOU WITH
DIFFERENT OR INCONSISTENT INFORMATION, YOU SHOULD NOT RELY ON IT. YOU SHOULD NOT
ASSUME THAT THE INFORMATION IN THIS PROSPECTUS IS ACCURATE AS OF ANY DATE OTHER
THAN THE DATE ON THE FRONT OF THIS DOCUMENT.

    REFERENCES IN THIS PROSPECTUS TO THE TERMS "WE," "OUR" OR "US" OR OTHER
SIMILAR TERMS MEAN IRON MOUNTAIN INCORPORATED AND ITS CONSOLIDATED SUBSIDIARIES,
UNLESS WE STATE OTHERWISE OR THE CONTEXT INDICATES OTHERWISE. REFERENCES IN THIS
PROSPECTUS TO "IM CAPITAL TRUST" MEANS IM CAPITAL TRUST I.

              CAUTIONARY NOTE REGARDING FORWARD-LOOKING STATEMENTS

    We have made and incorporated by reference statements in this document that
constitute "forward-looking statements" as that term is defined in the federal
securities laws. These forward-looking statements concern our operations,
economic performance and financial condition. The forward-looking statements are
subject to various known and unknown risks, uncertainties and other factors.
When we use words such as "believes," "expects," "anticipates," "estimates" or
similar expressions, we are making forward-looking statements.

    Although we believe that our forward-looking statements are based on
reasonable assumptions, our expected results may not be achieved and actual
results may differ materially from our expectations. Important factors that
could cause actual results to differ from expectations include, among others,
those set forth below. For a more detailed discussion of some of these factors,
please read carefully the information under "Risk Factors" beginning on page 2.

    - difficulties related to the integration of acquisitions generally and,
      more specifically, the integration of our operations and those of Pierce
      Leahy Corp.;

    - unanticipated costs as a result of our acquisition of Pierce Leahy;

    - the uncertainties related to international expansion and operations;

    - the uncertainties related to expansion into digital businesses, including
      the timing of introduction and market acceptance of our products and
      services;

    - rapid and significant changes in technology;

    - the cost and availability of appropriate storage facilities;

    - changes in customer preferences and demand for our services;

    - our significant indebtedness and the cost and availability of financing
      for contemplated growth; and

    - other general economic and business conditions.

    These cautionary statements should not be construed by you to be exhaustive
and they are made only as of the date of this prospectus. You should read these
cautionary statements as being applicable to all forward-looking statements
wherever they appear. We assume no obligation to update or revise the
forward-looking statements or to update the reasons why actual results could
differ from those projected in the forward-looking statements.

                                      (ii)
<Page>
                                  OUR COMPANY

    We are the leader in records and information management services. We are an
international, full-service provider of records and information management and
related services, enabling customers to outsource these functions. We have a
diversified customer base, which includes more than half of the Fortune 500 and
numerous commercial, legal, banking, healthcare, accounting, insurance,
entertainment and government organizations. We provide storage for all major
media, including paper, which is the dominant form of records storage, magnetic
media, including computer tapes, microfilm and microfiche, master audio and
video tapes, film and optical disks, X-rays and blueprints. Our principal
services provided to our storage customers include courier pick-up and delivery,
filing, retrieval and destruction of records, database management, customized
reporting and disaster recovery support. We also sell storage materials,
including cardboard boxes and magnetic media, and provide confidential
destruction, consulting, facilities management, fulfillment and other
outsourcing services.

    As of December 31, 2001, we provided services to over 125,000 customer
accounts in 80 markets in the United States and 44 markets outside of the United
States. We employ over 10,000 people and operate more than 650 records
management facilities in the United States, Canada, Europe and Latin America.

                                IM CAPITAL TRUST

    IM Capital Trust is a subsidiary of ours. IM Capital Trust was created under
the Delaware Business Trust Act and is governed by a declaration of trust, as it
may be amended and restated from time to time, among the trustees of IM Capital
Trust and us.

    When IM Capital Trust issues its trust preferred securities, the holders of
the trust preferred securities will own all of the issued and outstanding trust
preferred securities of IM Capital Trust. We will acquire all of the issued and
outstanding trust common securities of IM Capital Trust, representing an
undivided beneficial interest in the assets of IM Capital Trust of at least 3%.

    IM Capital Trust will exist primarily for the purposes of:

    - issuing its trust preferred and trust common securities;

    - investing the proceeds from the sale of its trust preferred and trust
      common securities in our debt securities; and

    - engaging in other activities only as are necessary or incidental to
      issuing its securities and purchasing and holding our debt securities.

    The debt securities IM Capital Trust purchases from us may be subordinated
debt securities or senior debt securities, and may be fully and unconditionally
guaranteed by substantially all of our present and future wholly owned domestic
subsidiaries. We will specify the type of debt security in a prospectus
supplement.

    IM Capital Trust has three trustees. One of the trustees, referred to as the
regular trustee, is an individual who is an officer and employee of Iron
Mountain. Additional regular trustees may be appointed in the future. The second
trustee is The Bank of New York, which serves as the property trustee under the
declaration of trust for purposes of the Trust Indenture Act of 1939. The third
trustee is The Bank of New York (Delaware), which has its principal place of
business in the State of Delaware, and serves as the Delaware trustee of IM
Capital Trust.

    The Bank of New York, acting in its capacity as guarantee trustee, will hold
for the benefit of the holders of trust preferred securities a trust preferred
securities guarantee, which will be separately qualified under the Trust
Indenture Act of 1939.

                                      -1-
<Page>
    Unless otherwise provided in the applicable prospectus supplement, because
we will own all of the trust common securities of IM Capital Trust, we will have
the exclusive right to appoint, remove or replace trustees and to increase or
decrease the number of trustees. In most cases, there will be at least three
trustees. The term of IM Capital Trust will be described in the applicable
prospectus supplement, but may dissolve earlier, as provided in IM Capital
Trust's declaration of trust, as it may be amended and restated from time to
time.

    The rights of the holders of the trust preferred securities of IM Capital
Trust, including economic rights, rights to information and voting rights and
the duties and obligations of the trustees of IM Capital Trust, will be
contained in and governed by the declaration of trust of IM Capital Trust, as it
may be amended and restated from time to time, the Delaware Business Trust Act
and the Trust Indenture Act of 1939.

                                  RISK FACTORS

    YOU SHOULD CONSIDER CAREFULLY THE FOLLOWING FACTORS AND OTHER INFORMATION IN
THIS PROSPECTUS BEFORE DECIDING TO INVEST IN OUR SECURITIES.

ACQUISITION AND INTERNATIONAL EXPANSION RISKS

FAILURE TO SUCCESSFULLY INTEGRATE ACQUIRED OPERATIONS COULD REDUCE OUR FUTURE
RESULTS OF OPERATIONS.

    The success of any acquisition depends in part on our ability to integrate
the acquired company. The process of integrating acquired businesses may involve
unforeseen difficulties and may require a disproportionate amount of our
management's attention and our financial and other resources.

    In particular, the integration of our operations and the operations formerly
conducted under the name Pierce Leahy has presented and will continue to present
a significant challenge to our management. We began integrating the cultures,
operating systems, procedures and information technologies of Iron Mountain and
Pierce Leahy approximately two years ago. The integration process is continuing
and will proceed for up to one more year.

    We can give no assurance that we will ultimately be able to effectively
integrate and manage the operations of any acquired business, in general, and
Pierce Leahy, in particular. Nor can we assure you that we will be able to
maintain or improve the historical financial performance of Iron Mountain,
Pierce Leahy or our other acquisitions. The failure to successfully integrate
these cultures, operating systems, procedures and information technologies could
have a material adverse effect on our results of operations.

FAILURE TO ACHIEVE EXPECTED COST SAVINGS AND UNANTICIPATED COSTS RELATED TO
INTEGRATING ACQUIRED COMPANIES COULD ADVERSELY AFFECT OUR RESULTS OF OPERATIONS.

    Our estimates of annual operating cost savings for acquired companies are a
function of the nature and timing of individual acquisition integration plans.
These savings result primarily from the elimination of redundant corporate
expenses and more efficient operations and utilization of real estate. However,
unanticipated future operating expenses or acquisition related expenses, or
other adverse developments, could reduce or delay realization of these cost
savings and materially affect our results of operations. The integration of
Pierce Leahy poses a particular risk due to the size and complexity of the
integration plan.

    Our operating results may fluctuate from quarter to quarter due to the
integration of current and future acquisitions. It is difficult to precisely
forecast the magnitude and timing of integration and merger-related expenses.
These expenses may be material to the financial results of a given quarter.

                                      -2-
<Page>
Therefore, operating results for any fiscal quarter may not be indicative of the
results that may be achieved for any subsequent quarter or for a full fiscal
year.

WE MAY BE UNABLE TO CONTINUE OUR INTERNATIONAL EXPANSION.

    Our growth strategy involves expanding operations into international
markets, and we expect to continue this expansion. Europe and Latin America have
been our primary areas of focus for international expansion. We have entered
into joint ventures and have acquired all or a majority of the equity in records
and information management services businesses operating in these areas and are
actively pursuing additional opportunities. This growth strategy involves risks.
We may be unable to pursue this strategy in the future. For example, we may be
unable to:

    - identify suitable companies to acquire;

    - complete acquisitions on satisfactory terms;

    - incur additional debt necessary to acquire suitable companies if we are
      unable to pay the purchase price out of working capital, common stock or
      other equity securities; or

    - enter into successful business arrangements for technical assistance or
      management and acquisition expertise outside of the United States.

    We also compete with other records and information management services
providers for companies to acquire. Some of our competitors may possess greater
financial and other resources than we do. If any such competitor were to devote
additional resources to such acquisition candidates or focus its strategy on our
international markets, our results of operations could be adversely affected.

WE MAY NOT BE ABLE TO EFFECTIVELY EXPAND OUR DIGITAL BUSINESSES.

    We have implemented the early stages of our planned expansion into various
digital businesses. Our entrance into these markets poses certain unique risks.
For example, we may be unable to:

    - raise the amount of capital necessary to effectively participate in these
      businesses;

    - develop, hire or otherwise obtain the necessary technical expertise;

    - accurately predict the size of the markets for any of these services; or

    - compete effectively against other companies who possess greater technical
      expertise, capital or other necessary resources.

    In addition, the business partners upon whom we depend for technical and
management expertise, as well as the hardware and software products we need to
complement our services, may not perform as expected.

OPERATIONAL RISKS

WE HAVE A HISTORY OF NET LOSSES.

    Our net losses are primarily attributable to significant non-cash charges
and interest expense associated with our acquisition and growth strategies. The
non-cash charges consist primarily of:

    - depreciation expenses associated with the expansion of storage capacity;
      and

    - goodwill amortization associated with acquisitions accounted for under the
      purchase method.

                                      -3-
<Page>
    Our primary financial goal has been, and will continue to be, to increase
consolidated Adjusted EBITDA(1) in relation to capital invested, even as we
shift our focus from growth through acquisitions to internal revenue growth. We
define Adjusted EBITDA as EBITDA (earnings before interest, taxes, depreciation
and amortization) adjusted for other income (expense), merger-related expenses,
stock option compensation expense and minority interest. Adjusted EBITDA is a
source of funds for investment in continued growth and for servicing debt.

    Having an objective of increasing consolidated Adjusted EBITDA may
negatively affect other measures of financial performance, such as net income.
In addition, execution of our growth strategy could result in future net losses
due to increased interest expense associated with borrowings and increased
depreciation and amortization expenses.

OUR CUSTOMERS MAY SHIFT FROM PAPER STORAGE TO ALTERNATIVE TECHNOLOGIES THAT
REQUIRE LESS PHYSICAL SPACE.

    We derive most of our revenues from the storage of paper documents and
related services. This storage requires significant physical space. Alternative
storage technologies exist, many of which require significantly less space than
paper. These technologies include computer media, microform, CD-ROM and optical
disk. To date, none of these technologies has replaced paper as the principal
means for storing information. However, we can provide no assurance that our
customers will continue to store most of their records in paper format. A
significant shift by our customers to storage of data through non-paper based
technologies, whether now existing or developed in the future, could adversely
affect our business.

WE MAY BE SUBJECT TO CERTAIN COSTS AND POTENTIAL LIABILITIES ASSOCIATED WITH THE
REAL ESTATE REQUIRED FOR OUR BUSINESSES.

    Because our businesses are heavily dependent on real estate, we face special
risks attributable to the real estate we own or operate. Such risks include:

    - variable occupancy costs and difficulty locating suitable sites due to
      fluctuations in the real estate market;

    - uninsured losses or damage to our storage facilities due to an inability
      to obtain full coverage on a cost-effective basis for some casualties,
      such as earthquakes, or any coverage for certain losses, such as losses
      from riots or terrorist activities;

    - loss of our investment in, and anticipated profits and cash flow from,
      damaged property that is uninsured;

    - liability under certain environmental laws for the costs of investigation
      and cleanup of contaminated real estate owned or leased by us, whether or
      not we know of, or were responsible for, the contamination, or the
      contamination occurred while we owned or leased the property;

- ------------------------

1   Adjusted EBITDA and Adjusted EBITDA-based calculations are used by the
    holders of our publicly issued debt as important criteria for evaluating our
    business and, as a result, all of our bond indentures contain covenants in
    which Adjusted EBITDA-based calculations are used as the primary measure of
    financial performance. In addition, we use Adjusted EBITDA as the basis for
    evaluating the performance of and allocating resources to our internal
    operating segments. However, you should not consider EBITDA or Adjusted
    EBITDA to be substitutes for operating or net income (as determined in
    accordance with generally accepted accounting principles, or GAAP) as
    indicators of our performance or to cash flow from operations (as determined
    in accordance with GAAP) as measures of liquidity.

                                      -4-
<Page>
    - third party claims resulting from the off-site migration of contamination
      initiating on real estate that we own or operate, or exposure to hazardous
      substances, including asbestos-containing materials, located on our
      property; and

    - an inability to sell, rent, mortgage or use contaminated real estate owned
      or leased by us.

    Some of our current and formerly owned or operated properties were
previously used for industrial or other purposes that involved the use, storage,
generation and/or disposal of hazardous substances and wastes and petroleum
products. In some instances these properties included the operation of
underground storage tanks. Although we have from time to time conducted limited
environmental investigations and remedial activities at some of our former and
current facilities, we have not undertaken an in-depth environmental review of
all of our properties. We therefore may be potentially liable for environmental
costs like those discussed above.

INTERNATIONAL OPERATIONS MAY POSE UNIQUE RISKS.

    As of December 31, 2001, we provided services in 44 markets outside the
United States. As part of our growth strategy, we expect to continue to acquire
records and information management services businesses in foreign markets.
International operations are subject to numerous risks, including:

    - the risk that the business partners upon whom we depend for technical
      assistance or management and acquisition expertise outside of the United
      States will not perform as expected;

    - the impact of foreign government regulations;

    - the volatility of certain foreign economies in which we operate;

    - political uncertainties;

    - differences in business practices; and

    - foreign currency fluctuations.

    In particular, our net income can be significantly affected by fluctuations
in foreign currencies associated with the U.S. dollar denominated debt of some
of our foreign subsidiaries and certain intercompany balances between our
domestic entities and our foreign subsidiaries.

WE FACE COMPETITION FOR CUSTOMERS.

    We compete with our current and potential customers' internal records and
information management services capabilities. We can provide no assurance that
these organizations will begin or continue to use an outside company, such as
our company, for their future records and information management services needs
or that they will use us to provide these services. We also compete with
multiple records and information management services providers in all geographic
areas where we operate.

INDEBTEDNESS AND OTHER RISKS

OUR SUBSTANTIAL INDEBTEDNESS COULD ADVERSELY AFFECT OUR FINANCIAL HEALTH.

    We have substantial indebtedness, which could have important consequences to
you. The risks associated with our substantial indebtedness include:

    - sensitivity to adverse economic conditions;

    - inability to fund future working capital, acquisitions, capital
      expenditures and other general corporate requirements;

                                      -5-
<Page>
    - limits on our flexibility in planning for, or reacting to, changes in our
      business and the records and information management services industry;

    - limits on future borrowings under our existing or future credit
      arrangements, which could affect our ability to pay our indebtedness or to
      fund our other liquidity needs;

    - inability to generate sufficient funds to cover required interest or
      principal amortization payments; and

    - restrictions on our ability to refinance our indebtedness on commercially
      reasonably terms.

    Our indebtedness may increase as we continue to borrow under existing and
future credit arrangements in order to finance future acquisitions and for
general corporate purposes, which would increase the associated risks.

RESTRICTIVE LOAN COVENANTS MAY LIMIT OUR ABILITY TO PURSUE OUR GROWTH STRATEGY.

    Our credit facility and our indentures contain covenants restricting or
limiting our ability to, among other things:

    - incur additional indebtedness;

    - pay dividends or make other restricted payments;

    - make asset dispositions;

    - create or permit liens; and

    - make capital expenditures and other investments.

    These restrictions may adversely affect our ability to pursue our
acquisition and other growth strategies.

CERTAIN PROVISIONS IN OUR GOVERNING DOCUMENTS AND INDENTURES, AND THE
COMPOSITION OF OUR SHAREHOLDERS, MIGHT DISCOURAGE OR PREVENT THIRD PARTIES FROM
ACQUIRING CONTROL OF OUR OUTSTANDING CAPITAL STOCK.

    Certain provisions of our articles of incorporation, our bylaws and existing
indentures might discourage or prevent a third party from acquiring actual or
potential control of us by:

    - making it more difficult to consummate certain types of transactions such
      as mergers, tender offers or proxy contests;

    - limiting shareholders' ability to quickly change the composition of our
      board of directors due to our classified board of directors;

    - allowing existing management to exercise significant control over our
      affairs during periods where we are threatened by a change in control;

    - allowing our board of directors to issue shares of preferred stock in the
      future without further shareholder approval and with full discretion as to
      terms, conditions, rights, privileges and preferences; and

    - requiring that we offer to purchase all or some of our outstanding senior
      subordinated notes and other publicly issued notes in certain
      circumstances that amount to a change of control under our indentures.

                                      -6-
<Page>
    In addition, because relatively few large shareholders control a significant
percentage of our voting power, these shareholders may:

    - prevent certain types of transactions involving an actual or potential
      change of control of us, including transactions made at prices above the
      prevailing market price of our common stock; and

    - significantly affect the election of our directors who, in turn, control
      our management and affairs.

                       RATIO OF EARNINGS TO FIXED CHARGES

    The following table sets forth our consolidated ratio of earnings to fixed
charges for the periods indicated (dollars in thousands):

<Table>
<Caption>
                                                                                                    NINE MONTHS ENDED
                                                           YEAR ENDED DECEMBER 31,                    SEPTEMBER 30,
                                             ----------------------------------------------------   -----------------
                                               1996       1997       1998       1999       2000           2001
                                             --------   --------   --------   --------   --------   -----------------
                                                                                  
Ratio of earnings to fixed charges.........    1.1x      0.9x(1)     1.1x       1.1x      0.9x(1)         0.9x(1)
</Table>

- ------------------------

(1) We reported a loss from continuing operations before provision (benefit) for
    income taxes and minority interest, for the years ended December 31, 1997
    and December 31, 2000 and for the nine months ended September 30, 2001. We
    would have needed to generate additional income from operations before
    provision for income taxes and minority interest of $4,601, $18,032 and
    $7,786 to cover our fixed charges of $37,489, $154,975 and $133,292,
    respectively.

    The ratios of earnings to fixed charges presented above were computed by
dividing our earnings by fixed charges. For this purpose, earnings have been
calculated by adding fixed charges to income (loss) from continuing operations
before provision (benefit) for income taxes and minority interest. Fixed charges
consist of interest costs, whether expensed or capitalized, the interest
component of rental expense, if any, amortization of debt discounts and deferred
financing costs, whether expensed or capitalized.

                                      -7-
<Page>
                                USE OF PROCEEDS

    Unless otherwise described in a prospectus supplement, we intend to use the
net proceeds from the sale of the offered securities for general corporate
purposes, which may include acquisitions, investments and the repayment of
indebtedness outstanding at a particular time. Pending this utilization, the
proceeds from the sale of the offered securities will be invested in short-term,
dividend-paying or interest-bearing investment grade securities.

    IM Capital Trust will use all net proceeds from the sale of its trust
preferred securities and its trust common securities to purchase our debt
securities.

                       DESCRIPTION OF OUR DEBT SECURITIES

    The debt securities will be direct obligations of ours, which may be secured
or unsecured, and which may be senior or subordinated indebtedness. The debt
securities may be fully and unconditionally guaranteed on a secured or
unsecured, senior or subordinated basis, jointly and severally by substantially
all of our direct and indirect wholly owned domestic subsidiaries. The debt
securities will be issued under one or more indentures between us and a trustee.
Any indenture will be subject to, and governed by, the Trust Indenture Act of
1939, as amended. The statements made in this prospectus relating to any
indentures and the debt securities to be issued under the indentures are
summaries of certain anticipated provisions of the indentures and are not
complete.

    We have filed copies of the forms of indentures as exhibits to the
registration statement of which this prospectus is part and will file any final
indentures and supplemental indentures if we issue debt securities. You should
refer to those indentures for the complete terms of the debt securities. See
"Where You Can Find More Information." In addition, you should consult the
applicable prospectus supplement for particular terms of our debt securities.

GENERAL

    We may issue debt securities that rank "senior," "senior subordinated" or
"subordinated." The debt securities that we refer to as "senior securities" will
be direct obligations of ours and will rank equally and ratably in right of
payment with other indebtedness of ours that is not subordinated. We may issue
debt securities that will be subordinated in right of payment to the prior
payment in full of senior indebtedness, as defined in the applicable prospectus
supplement, and may rank equally and ratably with our outstanding senior
subordinated indebtedness and any other senior subordinated indebtedness. We
refer to these as "senior subordinated securities." We may also issue debt
securities that may be subordinated in right of payment to the senior
subordinated securities. These would be "subordinated securities." We have filed
with the registration statement of which this prospectus is part three separate
forms of indenture, one each for the senior securities, the senior subordinated
securities and the subordinated securities.

    We may issue the debt securities without limit as to aggregate principal
amount, in one or more series, in each case as we establish in one or more
supplemental indentures. We need not issue all debt securities of one series at
the same time. Unless we otherwise provide, we may reopen a series, without the
consent of the holders of such series, for issuances of additional securities of
that series.

    We anticipate that any indenture will provide that we may, but need not,
designate more than one trustee under an indenture, each with respect to one or
more series of debt securities. Any trustee under any indenture may resign or be
removed with respect to one or more series of debt securities and we may appoint
a successor trustee to act with respect to that series.

                                      -8-
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    The applicable prospectus supplement will describe the specific terms
relating to the series of debt securities we will offer, including, where
applicable, the following:

    - the title and series designation and whether they are senior securities,
      senior subordinated securities or subordinated securities;

    - the aggregate principal amount of the securities;

    - the percentage of the principal amount at which we will issue the debt
      securities and, if other than the principal amount of the debt securities,
      the portion of the principal amount of the debt securities payable upon
      maturity of the debt securities;

    - if convertible, the initial conversion price, the conversion period and
      any other terms governing such conversion;

    - the stated maturity date;

    - any fixed or variable interest rate or rates per annum;

    - the place where principal, premium, if any, and interest will be payable
      and where the debt securities can be surrendered for transfer, exchange or
      conversion;

    - the date from which interest may accrue and any interest payment dates;

    - any sinking fund requirements;

    - any provisions for redemption, including the redemption price and any
      remarketing arrangements;

    - whether the securities are denominated or payable in U.S. dollars or a
      foreign currency or units of two or more foreign currencies;

    - the events of default and covenants of such securities, to the extent
      different from or in addition to those described in this prospectus;

    - whether we will issue the debt securities in certificated or book-entry
      form;

    - whether the debt securities will be in registered or bearer form and, if
      in registered form, the denominations if other than in even multiples of
      $1,000 and, if in bearer form, the denominations and terms and conditions
      relating thereto;

    - whether we will issue any of the debt securities in permanent global form
      and, if so, the terms and conditions, if any, upon which interests in the
      global security may be exchanged, in whole or in part, for the individual
      debt securities represented by the global security;

    - the applicability, if any, of the defeasance and covenant defeasance
      provisions described in this prospectus or any prospectus supplement;

    - whether we will pay additional amounts on the securities in respect of any
      tax, assessment or governmental charge and, if so, whether we will have
      the option to redeem the debt securities instead of making this payment;

    - the subordination provisions, if any, relating to the debt securities;

    - if the debt securities are to be issued upon the exercise of debt
      warrants, the time, manner and place for them to be authenticated and
      delivered;

    - whether any of our subsidiaries will be bound by the terms of the
      indenture, in particular any restrictive covenants;

    - the provisions relating to any security provided for the debt securities;
      and

    - the provisions relating to any guarantee of the debt securities.

                                      -9-
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    We may issue debt securities at less than the principal amount payable upon
maturity. We refer to these securities as "original issue discount securities."
If material or applicable, we will describe in the applicable prospectus
supplement special U.S. federal income tax, accounting and other considerations
applicable to original issue discount securities.

    Except as may be set forth in any prospectus supplement, an indenture will
not contain any other provisions that would limit our ability to incur
indebtedness or that would afford holders of the debt securities protection in
the event of a highly leveraged or similar transaction involving us or in the
event of a change of control. You should review carefully the applicable
prospectus supplement for information with respect to events of default and
covenants applicable to the securities being offered.

DENOMINATIONS, INTEREST, REGISTRATION AND TRANSFER

    Unless otherwise described in the applicable prospectus supplement, we will
issue the debt securities of any series that are registered securities in
denominations that are even multiples of $1,000, other than global securities,
which may be of any denomination.

    Unless otherwise specified in the applicable prospectus supplement, we will
pay the interest, principal and any premium at the corporate trust office of the
trustee. At our option, however, we may make payment of interest by check mailed
to the address of the person entitled to the payment as it appears in the
applicable register or by wire transfer of funds to that person at an account
maintained within the United States.

    If we do not punctually pay or duly provide for interest on any interest
payment date, the defaulted interest will be paid either:

    - to the person in whose name the debt security is registered at the close
      of business on a special record date we will fix; or

    - in any other lawful manner as the applicable indenture describes.

    You may have your debt securities divided into more debt securities of
smaller denominations or combined into fewer debt securities of larger
denominations, as long as the total principal amount is not changed. We call
this an "exchange."

    You may exchange or transfer debt securities at the office of the applicable
trustee. The trustee acts as our agent for registering debt securities in the
names of holders and transferring debt securities. We may change this
appointment to another entity or perform it ourselves. The entity performing the
role of maintaining the list of registered holders is called the "registrar." It
will also perform transfers.

    You will not be required to pay a service charge to transfer or exchange
debt securities, but you may be required to pay for any tax or other
governmental charge associated with the exchange or transfer. The registrar will
make the transfer or exchange only if it is satisfied with your proof of
ownership.

MERGER, CONSOLIDATION OR SALE OF ASSETS

    Under any indenture, we are generally permitted to consolidate or merge with
another company. We are also permitted to sell substantially all of our assets
to another company. However, we may not take any of these actions unless all of
the following conditions are met:

    - If we merge out of existence or sell our assets, the other company must be
      a corporation, partnership or other entity organized under the laws of a
      State or the District of Columbia or under federal law. The other company
      must agree to be legally responsible for the debt securities.

                                      -10-
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    - Immediately after the consolidation or merger or sale of assets we are not
      in default on the debt securities. A default for this purpose would
      include any event that would be an event of default without regard to
      notice obligations or the length of time of the default.

CERTAIN COVENANTS

    PROVISION OF FINANCIAL INFORMATION.  We will deliver to the trustee a copy
of our annual report to shareholders, our reports on Forms 10-K, 10-Q and 8-K
and any other reports that we are required to file with the SEC pursuant to
Section 13 or 15(d) of the Securities Exchange Act of 1934.

    ADDITIONAL COVENANTS.  Any additional or different covenants, or
modifications to these covenants, with respect to any series of debt securities
will be set forth in the applicable prospectus supplement.

EVENTS OF DEFAULT AND RELATED MATTERS

    EVENTS OF DEFAULT.  The term "event of default" means any of the following:

    - we do not pay the principal or any premium on a debt security on its due
      date;

    - we do not pay interest on a debt security within 30 days of its due date;

    - we do not deposit any sinking fund payment on its due date;

    - we fail to comply with any "change of control" covenant included in the
      applicable indenture;

    - we remain in breach of any other term of the applicable indenture for
      60 days after we receive a notice of default stating we are in breach.
      Either the trustee or the holders of 25% in principal amount of debt
      securities of the affected series may send the notice;

    - we default in the payment of any of our other indebtedness over a
      specified amount that results in the acceleration of the maturity of the
      indebtedness or constitutes a default in the payment of the indebtedness
      at final maturity, but only if the indebtedness is not discharged or the
      acceleration is not rescinded or annulled;

    - we or one of our "significant subsidiaries" files for bankruptcy or
      certain other events in bankruptcy, insolvency or reorganization occur;
      and

    - any other event of default, or modification of any of the foregoing events
      of default, described in the applicable prospectus supplement occurs.

    The term "significant subsidiary" means each of our significant subsidiaries
(as defined in Regulation S-X promulgated under the Securities Act of 1933).

    REMEDIES IF AN EVENT OF DEFAULT OCCURS.  If an event of default has occurred
and has not been cured, the trustee or the holders of at least 25% in principal
amount of the debt securities of the affected series may declare the entire
principal amount of all the debt securities of that series to be due and
immediately payable. We call this a "declaration of acceleration of maturity."
If an event of default occurs because of certain events in bankruptcy,
insolvency or reorganization, the principal amount of all the debt securities of
that series will be automatically accelerated, without any action by the trustee
or any holder. At any time after the trustee or the holders have accelerated any
series of debt securities, the holders of at least a majority in principal
amount of the debt securities of the affected series may, under certain
circumstances, rescind and annul such acceleration.

    The trustee will be required to give notice to the holders of debt
securities within 90 days of a default of which the trustee has knowledge under
the applicable indenture unless the default has been cured or waived. The
trustee may withhold notice to the holders of any series of debt securities of
any default with respect to that series, except a default in the payment of the
principal of or interest on any

                                      -11-
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debt security of that series, if specified responsible officers of the trustee
in good faith determine that withholding the notice is in the interest of the
holders.

    Except in cases of default, where the trustee has some special duties, the
trustee is not required to take any action under the applicable indenture at the
request of any holders unless the holders offer the trustee reasonable
protection from expenses and liability. We refer to this as an "indemnity." If
reasonable indemnity is provided, the holders of a majority in principal amount
of the outstanding securities of the relevant series may direct the time, method
and place of conducting any lawsuit or other formal legal action seeking any
remedy available to the trustee. These majority holders may also direct the
trustee in performing any other action under the applicable indenture, subject
to certain limitations.

    Before you bypass the trustee and bring your own lawsuit or other formal
legal action or take other steps to enforce your rights or protect your
interests relating to the debt securities, the following must occur:

    - you must give the trustee written notice that an event of default has
      occurred and remains uncured;

    - the holders of at least 25% in principal amount of all outstanding
      securities of the relevant series must make a written request that the
      trustee take action because of the default, and must offer indemnity
      satisfactory to the trustee against the costs, expenses and other
      liabilities of taking that action;

    - the trustee must have not taken action for 60 days after receipt of the
      above notice, request and offer of indemnity; and

    - the trustee does not receive direction contrary to the holders' written
      request, within 60 days following receipt of the holders' written request,
      from holders of a majority in principal amount of the outstanding
      securities of that series.

    However, you are entitled at any time to bring a lawsuit for the payment of
money due on your security after its due date.

    Every year we will furnish to the trustee a written statement by certain of
our officers certifying that to their knowledge we are in compliance with the
applicable indenture and the debt securities, or else specifying any default.

MODIFICATION OF AN INDENTURE

    There are three types of changes we can make to the indentures and the debt
securities:

    CHANGES REQUIRING YOUR APPROVAL.  First, there are changes we cannot make to
your debt securities without your specific approval. The following is a list of
those types of changes:

    - reduce the principal amount of debt securities whose holders must consent
      to an amendment, supplement or waiver;

    - reduce the principal of or change the fixed maturity of any security or
      change any of the redemption provisions in a manner adverse to you;

    - reduce the rate of or change the time for payment of interest on any debt
      security;

    - waive a default in the payment of principal of or premium, if any, or
      interest on any debt security (except a rescission of acceleration of such
      debt securities by the holders of at least a majority in aggregate
      principal amount of the then outstanding debt securities and a waiver of
      the payment default that resulted from such acceleration);

                                      -12-
<Page>
    - make any debt security payable in money other than that stated in such
      debt security;

    - make any change in the provisions of the indenture relating to waivers of
      past defaults or your right to receive payments of principal of or
      premium, if any, or interest on the debt securities;

    - except under certain circumstances described in the applicable prospectus
      supplement, waive a redemption payment with respect to any debt security;

    - if the debt securities are guaranteed, other than as described in the
      applicable prospectus supplement, release any guarantor from its
      obligations under its subsidiary guarantee, or change any subsidiary
      guarantee in any manner that would materially adversely affect you; or

    - make any change in the foregoing amendment and waiver provisions.

    CHANGES REQUIRING A MAJORITY VOTE.  The second type of change to an
indenture and the debt securities is the kind that requires a vote in favor by
holders of a majority of the principal amount of the particular series of debt
securities affected. Most changes fall into this category, except for clarifying
changes and certain other changes that would not materially adversely affect
holders of the debt securities. We require the same vote to obtain a waiver of a
past default. However, we cannot obtain a waiver of a payment default or any
other aspect of an indenture or the debt securities listed under "--Changes
Requiring Your Approval" unless we obtain your individual consent to the waiver.

    CHANGES NOT REQUIRING APPROVAL.  The third type of change does not require
any vote by holders of debt securities. This type is limited to clarifications
and certain other changes that would not materially adversely affect holders of
the debt securities.

    FURTHER DETAILS CONCERNING VOTING.  Debt securities are not considered
outstanding, and therefore not eligible to vote, if we have deposited or set
aside in trust for you money for their payment or redemption or if we or one of
our affiliates own them. Debt securities are also not eligible to vote if they
have been fully defeased as described immediately below under "--Discharge,
Defeasance and Covenant Defeasance--Full Defeasance." For original issue
discount securities, we will use the principal amount that would be due and
payable on the voting date if the maturity of the debt securities were
accelerated to that date because of a default.

DEFEASANCE AND COVENANT DEFEASANCE

    FULL DEFEASANCE.  We can, under particular circumstances, effect a full
defeasance of your series of debt securities. By this we mean we can legally
release ourselves from any payment or other obligations on the debt securities
if we deliver certain certificates and opinions to the trustee and put in place
the following arrangements to repay you:

    - We must deposit in trust for your benefit and the benefit of all other
      direct holders of the debt securities a combination of money and U.S.
      government or U.S. government agency notes or bonds that will generate
      enough cash to make interest, principal and any other payments on the debt
      securities on their various due dates. If the debt securities are
      denominated in a foreign currency, then we may deposit foreign government
      notes or bonds.

    - The current federal tax law must be changed or an IRS ruling must be
      issued permitting the above deposit without causing you to be taxed on the
      debt securities any differently than if we did not make the deposit and
      just repaid the debt securities ourselves. Under current federal tax law,
      the deposit and our legal release from the debt securities would be
      treated as though we took back your debt securities and gave you your
      share of the cash and notes or bonds deposited in trust. In that event,
      you could recognize gain or loss on the debt securities you give back to
      us.

    - We must deliver to the trustee a legal opinion confirming the tax law
      change described above.

                                      -13-
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    - No default shall be in effect on the date of deposit or, insofar as
      bankruptcy and insolvency defaults are concerned, at any time in the
      period ending on the 91st day after the date of deposit (or greater period
      of time in which any such deposit of trust funds may remain subject to
      bankruptcy law insofar as those apply to the deposit by us).

    - The full defeasance must not result in a breach or violation of, or
      constitute a default under, any material agreement or instrument (other
      than the applicable indenture) to which we are a party or by which we are
      bound.

    - We must deliver to the trustee an opinion of counsel to the effect that
      after the 91st day following the deposit, the trust funds will not be
      subject to the effect of any applicable bankruptcy, insolvency,
      reorganization or similar laws affecting creditors' rights generally and
      various other opinions of counsel and officers' certificates.

    If we did accomplish a full defeasance, you would have to rely solely on the
trust deposit for repayment on the debt securities. You could not look to us for
repayment in the unlikely event of any shortfall. The trust deposit would,
however, most likely be protected from claims of our lenders and other creditors
if we ever became bankrupt or insolvent. You would also be released from any
subordination provisions.

    Notwithstanding the foregoing, the following rights and obligations shall
survive full defeasance:

    - your rights to receive payments from the trust when payments are due;

    - our obligations relating to registration and transfer of securities and
      lost or mutilated certificates;

    - our obligations to maintain a payment office and to hold moneys for
      payment in trust;

    - the rights, powers, trusts, duties and immunities of the trustee, and our
      obligations in connection therewith; and

    - the provisions of the indenture relating to defeasance.

    COVENANT DEFEASANCE.  Under current federal tax law, we can make the same
type of deposit described above and be released from some of the restrictive
covenants in the debt securities. This is called "covenant defeasance." In that
event, you would lose the protection of those restrictive covenants but would
gain the protection of having money and securities set aside in trust to repay
the debt securities and you would be released from any subordination provisions.
In order to achieve covenant defeasance, we must do certain things, including
the following:

    - we must deposit in trust for your benefit and the benefit of all other
      direct holders of the debt securities a combination of money and U.S.
      government or U.S. government agency notes or bonds (or, in the case of
      debt securities denominated in a foreign currency, foreign government
      notes or bonds) that will generate enough cash to make interest, principal
      and any other payments on the debt securities on their various due dates;

    - we must deliver to the trustee a legal opinion confirming that under
      current federal tax law we may make the above deposit without causing you
      to be taxed on the debt securities any differently than if we did not make
      the deposit and just repaid the debt securities ourselves;

    - no default shall be in effect on the date of deposit or, insofar as
      bankruptcy and insolvency defaults are concerned, at any time in the
      period ending on the 91st day after the date of deposit (or greater period
      of time in which any such deposit of trust funds may remain subject to
      bankruptcy law insofar as those apply to the deposit by us);

                                      -14-
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    - the covenant defeasance must not result in a breach or violation of, or
      constitute a default under, any material agreement or instrument (other
      than the applicable indenture) to which we are a party or by which we are
      bound; and

    - we must deliver to the trustee an opinion of counsel to the effect that
      after the 91st day following the deposit, the trust funds will not be
      subject to the effect of any applicable bankruptcy, insolvency,
      reorganization or similar laws affecting creditors' rights generally and
      various other opinions of counsel and officers' certificates.

    If we accomplish covenant defeasance, we will be released from certain
covenants that we will describe in the applicable prospectus supplement. If we
accomplish covenant defeasance, you can still look to us for repayment of the
debt securities if a shortfall in the trust deposit occurred. If one of the
remaining events of default occurs, for example, our bankruptcy, and the debt
securities become immediately due and payable, there may be a shortfall.
Depending on the event causing the default, you may not be able to obtain
payment of the shortfall.

SUBORDINATION

    We will set forth in the applicable prospectus supplement the terms and
conditions, if any, upon which any series of senior subordinated securities or
subordinated securities is subordinated to debt securities of another series or
to other indebtedness of ours. The terms will include a description of:

    - the indebtedness ranking senior to the debt securities being offered;

    - the restrictions, if any, on payments to the holders of the debt
      securities being offered while a default with respect to the senior
      indebtedness is continuing;

    - the restrictions, if any, on payments to the holders of the debt
      securities being offered following an event of default; and

    - provisions requiring holders of the debt securities being offered to remit
      some payments to holders of senior indebtedness.

CONVERSION RIGHTS

    The terms and conditions, if any, upon which the debt securities are
convertible into shares of our common or preferred stock will be set forth in
the prospectus supplement relating thereto. Such terms will include whether the
debt securities are convertible into shares of our common or preferred stock,
the conversion price (or manner of calculation thereof), the conversion period,
provisions as to whether conversion will be at the option of the holders, the
events requiring an adjustment of the conversion price and provisions affecting
conversion in the event of the redemption of such debt securities and any
restrictions on conversion.

GLOBAL SECURITIES

    If so set forth in the applicable prospectus supplement, we may issue the
debt securities of a series, in whole or in part, in the form of one or more
global securities that will be deposited with a depositary identified in the
prospectus supplement. We may issue global securities in either registered or
bearer form and in either temporary or permanent form. The specific terms of the
depositary arrangement with respect to any series of debt securities will be
described in the prospectus supplement.

                                      -15-
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                        DESCRIPTION OF OUR CAPITAL STOCK

    The description below summarizes the more important terms of our capital
stock. We have previously filed with the SEC copies of our articles of
incorporation and bylaws, as amended. See "Where You Can Find More Information."
You should refer to those documents for the complete terms of our capital stock.
This summary is subject to and qualified by reference to the description of the
particular terms of your securities described in the applicable prospectus
supplement.

GENERAL

    Our authorized capital stock consists of 150,000,000 shares of common stock,
par value $.01 per share, and 10,000,000 shares of preferred stock, par value
$.01 per share.

PREFERRED STOCK

    We are authorized to issue up to 10,000,000 shares of preferred stock, $0.01
par value per share.

    This section describes the general terms and provisions of our preferred
stock that we may offer from time to time. The applicable prospectus supplement
will describe the specific terms of the shares of preferred stock offered
through that prospectus supplement. We will file a copy of the statement with
respect to shares that contains the terms of each new series of preferred stock
with the SEC each time we issue a new series of preferred stock, and these
statements with respect to shares will be incorporated by reference into the
registration statement of which this prospectus is a part. Each statement with
respect to shares will establish the number of shares included in a designated
series and fix the designation, powers, privileges, preferences and rights of
the shares of each series as well as any applicable qualifications, limitations
or restrictions. A holder of our preferred stock should refer to the applicable
statement with respect to shares, our articles of incorporation and the
applicable prospectus supplement for more specific information.

    Our board of directors has been authorized, subject to limitations provided
in our articles of incorporation, to provide for the issuance of shares of our
preferred stock in multiple series. No shares of our preferred stock are
currently outstanding.

    With respect to each series of our preferred stock, our board of directors
has the authority to fix the following terms:

    - the designation of the series;

    - the number of shares within the series;

    - whether dividends are cumulative and, if cumulative, the dates from which
      dividends are cumulative;

    - the rate of any dividends, any conditions upon which dividends are
      payable, and the dates of payment of dividends;

    - whether the shares are redeemable, the redemption price and the terms of
      redemption;

    - the amount payable to a holder for each share owned if we are dissolved or
      liquidated;

    - whether the shares are convertible or exchangeable, the price or rate of
      exchange, and the applicable terms and conditions;

    - any restrictions on issuance of shares in the same series or any other
      series; and

    - your voting rights for the shares you own.

    Holders of our preferred stock will not have preemptive rights with respect
to shares of our preferred stock. In addition, rights with respect to shares of
our preferred stock will be subordinate to

                                      -16-
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the rights of our general creditors. If we receive the appropriate payment,
shares of our preferred stock that we issue will be fully paid and
nonassessable.

    As described under "Description of Our Depositary Shares," we may, at our
option, elect to offer depositary shares evidenced by depositary receipts. If we
elect to do this, each depositary receipt will represent a fractional interest
in a share of the particular series of the preferred stock issued and deposited
with a depositary. The applicable prospectus supplement will specify that
fractional interest.

    We currently plan to retain EquiServe Trust Company, N.A. as the registrar
and transfer agent of any series of our preferred stock.

COMMON STOCK

    VOTING RIGHTS.  Holders of common stock are entitled to one vote per share
on each matter to be decided by our shareholders, subject to the rights of
holders of any series of preferred stock that may be outstanding from time to
time. Pursuant to our articles of incorporation, there are no cumulative voting
rights in the election of directors. Accordingly, the holders of a majority of
common stock entitled to vote in any election of directors may elect all of the
directors standing for election.

    DIVIDEND RIGHTS AND LIMITATIONS.  Holders of common stock will be entitled
to receive ratably any dividends or distributions that our board of directors
may declare from time to time out of funds legally available for this purpose.

    Dividends and other distributions on common stock are also subject to the
rights of holders of any series of preferred stock that may be outstanding from
time to time and to the restrictions in our credit agreement and indentures. See
"--Preferred Stock."

    LIQUIDATION RIGHTS.  In the event of liquidation, dissolution or winding up
of our affairs, after payment or provision for payment of all of our debts and
obligations and any preferential distributions to holders of shares of preferred
stock, if any, the holders of the common stock will be entitled to share ratably
in our remaining assets available for distribution.

    MISCELLANEOUS.  All outstanding shares of common stock are validly issued,
fully paid and nonassessable. Our board of directors has the power to issue
shares of authorized but unissued common stock without further shareholder
action. The issuance of these unissued shares could have the effect of diluting
the earnings per share and book value per share of currently outstanding shares
of common stock. The holders of common stock have no preemptive, subscription,
redemption or conversion rights.

    Reference is made to the applicable prospectus supplement relating to the
common stock offered by that prospectus supplement for specific terms,
including:

    - amount and number of shares offered;

    - the initial offering price, if any, and market price; and

    - information with respect to dividends.

    TRANSFER AGENT AND REGISTRAR.  The transfer agent and registrar for our
common stock is EquiServe Trust Company, N.A., 150 Royall Street, Canton,
Massachusetts 02021. Its telephone number is (781) 575-2000.

                                      -17-
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                      DESCRIPTION OF OUR DEPOSITARY SHARES

GENERAL

    The description shown below, and in any applicable prospectus supplement, of
certain provisions of any deposit agreement and of the depositary shares and
depositary receipts representing depositary shares does not purport to be
complete and is subject to and qualified in its entirety by reference to the
forms of deposit agreement and depositary receipts relating to each applicable
series of preferred stock. The deposit agreement and the depositary receipts
contain the full legal text of the matters described in this section. We will
file a copy of those documents with the SEC at or before the time of the
offering of the applicable series of preferred stock. This summary also is
subject to and qualified by reference to the description of the particular terms
of your series of depositary shares described in the applicable prospectus
supplement.

    We may, at our option, elect to offer depositary shares representing
fractional interests in shares of preferred stock, rather than shares of
preferred stock. If we exercise this option, we will appoint a depositary to
issue depositary receipts representing those fractional interests. Preferred
stock of each series represented by depositary shares will be deposited under a
separate deposit agreement between us and the depositary. The prospectus
supplement relating to a series of depositary shares will disclose the name and
address of the depositary. Subject to the terms of the applicable deposit
agreement, each holder of depositary shares will be entitled to all of the
distribution, voting, conversion, redemption, liquidation and other rights and
preferences of the preferred stock represented by those depositary shares.

    Depositary receipts issued pursuant to the applicable deposit agreement will
evidence ownership of depositary shares. Upon surrender of depositary receipts
at the office of the depositary, and upon payment of the charges provided in and
subject to the terms of the deposit agreement, a holder of depositary shares
will be entitled to receive the shares of preferred stock underlying the
surrendered depositary receipts.

DISTRIBUTIONS

    A depositary will be required to distribute all cash distributions received
in respect of the applicable preferred stock to the record holders of depositary
shares in proportion to the number of depositary shares held by the holders on
the relevant record date, which will be the same as the record date fixed by us
for the applicable series of preferred stock. Fractions will be rounded down to
the nearest whole cent.

    If the distribution is other than in cash, a depositary will be required to
distribute property received by it to the record holders of depositary shares
entitled thereto, in proportion, as nearly as practicable, to the number of
depositary shares owned by those holders on the relevant record date, unless the
depositary determines that it is not feasible to make the distribution. In that
case, the depositary may, with our approval, sell the property and distribute
the net proceeds from the sale to the holders.

    Depositary shares that represent preferred stock converted or exchanged will
not be entitled to distributions. The deposit agreement will also contain
provisions relating to the manner in which any subscription or similar rights we
offer to holders of the preferred stock will be made available to holders of
depositary shares. All distributions will be subject to obligations of holders
to file proofs, certificates and other information and to pay certain charges
and expenses to the depositary.

WITHDRAWAL OF PREFERRED STOCK

    Holders of depositary shares may receive the number of whole shares of the
applicable series of preferred stock and any money or other property represented
by those depositary shares after

                                      -18-
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surrendering the depositary receipts at the corporate trust office of the
depositary and paying the charges provided in the depositary agreement. Partial
shares of preferred stock will not be issued. If the depositary receipts that a
holder surrenders evidence a number of depositary shares in excess of the number
of depositary shares representing the number of whole shares of preferred stock
the holder wishes to withdraw, then the depositary will deliver to the holder at
the same time a new depositary receipt evidencing the excess number of
depositary shares. Once a holder has withdrawn the holder's preferred stock, the
holder will not be entitled to re-deposit those shares of preferred stock under
the deposit agreement in order to receive depositary shares. We do not expect
that there will be any public trading market for withdrawn shares of preferred
stock.

REDEMPTION OF DEPOSITARY SHARES

    If we redeem a series of the preferred stock underlying the depositary
shares, the depositary will redeem those depositary shares representing the
preferred stock so redeemed from the proceeds received by it in connection with
the redemption. The depositary will mail notice of redemption not less than 30
and not more than 60 days before the date fixed for redemption to the record
holders of the depositary shares we are redeeming at their addresses appearing
in the depositary's books. The redemption price per depositary share will be
equal to the applicable fraction of the redemption price per share payable with
respect to the series of the preferred stock. The redemption date for depositary
shares will be the same as that of the preferred stock. If we are redeeming less
than all of the depositary shares, the depositary will select the depositary
shares we are redeeming by lot or pro rata as the depositary may determine.

    After the date fixed for redemption, the depositary shares called for
redemption will no longer be deemed outstanding. All rights of the holders of
the depositary shares and the related depositary receipts will cease at that
time, except the right to receive the money or other property to which the
holders of depositary shares were entitled upon redemption. Receipt of the money
or other property is subject to surrender to the depositary of the depositary
receipts evidencing the redeemed depositary shares.

VOTING OF THE PREFERRED STOCK

    Upon receipt of notice of any meeting at which the holders of preferred
stock represented by depositary shares are entitled to vote, a depositary will
be required to mail the information contained in the notice of meeting to the
record holders of the applicable depositary shares. Each record holder of
depositary shares on the record date, which will be the same date as the record
date for the preferred stock, will be entitled to instruct the depositary as to
the exercise of the voting rights pertaining to the amount of preferred stock
represented by the holder's depositary shares. The depositary will try, as
practical, to vote the depositary shares as instructed by the record holder of
depositary shares. We will agree to take all reasonable action that the
depositary deems necessary in order to enable it to do so. If a record holder of
depositary shares does not instruct the depositary how to vote the holder's
depositary shares, the depositary will abstain from voting those shares.

LIQUIDATION PREFERENCE

    Upon our liquidation, whether voluntary or involuntary, each holder of
depositary shares will be entitled to the fraction of the liquidation preference
accorded each share of preferred stock represented by the depositary shares, as
shown in the applicable prospectus supplement.

CONVERSION OR EXCHANGE OF PREFERRED STOCK

    The depositary shares will not themselves be convertible into or
exchangeable for common stock, preferred stock or any of our other securities or
property. Nevertheless, if so specified in the applicable

                                      -19-
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prospectus supplement, the depositary receipts may be surrendered by holders to
the applicable depositary with written instructions to it to instruct us to
cause conversion of the preferred stock represented by the depositary shares.
Similarly, if so specified in the applicable prospectus supplement, we may
require holders of depositary shares to surrender all of their depositary
receipts to the applicable depositary upon our requiring the conversion or
exchange of the preferred stock represented by the depositary shares into a
different class of our securities. We will agree that, upon receipt of the
instruction and any amounts payable in connection with the conversion or
exchange, we will cause the conversion or exchange using the same procedures as
those provided for delivery of preferred stock to effect the conversion or
exchange. If a holder of depositary shares is converting only a part of the
depositary shares, the depositary will issue the holder a new depositary receipt
for any unconverted depositary shares.

TAXATION

    A holder of depositary shares will be treated for U.S. federal income tax
purposes as if it were a holder of the series of preferred stock represented by
the depositary shares. Therefore, the holder of depositary shares will be
required to take into account for U.S. federal income tax purposes income and
deductions to which it would be entitled if it were a holder of the underlying
series of preferred stock. In addition:

    - no gain or loss will be recognized for U.S. federal income tax purposes
      upon the withdrawal of preferred stock in exchange for depositary shares
      provided in the deposit agreement;

    - the tax basis of each share of preferred stock issued to a holder as
      exchanging owner of depositary shares will, upon exchange, be the same as
      the aggregate tax basis of the depositary shares exchanged for the
      preferred stock; and

    - if a holder held the depositary shares as a capital asset at the time of
      the exchange for preferred stock, the holding period for shares of the
      preferred stock will include the period during which the holder owned the
      depositary shares.

AMENDMENT AND TERMINATION OF A DEPOSIT AGREEMENT

    We and the applicable depositary are permitted to amend the form of the
depositary receipt and the provisions of the deposit agreement. However, the
holders of at least a majority of the applicable depositary shares then
outstanding must approve any amendment that adds or increases fees or materially
and adversely alters the rights of holders. Every holder of an outstanding
depositary receipt at the time any amendment becomes effective, by continuing to
hold the receipt, will be bound by the applicable deposit agreement, as amended.

    Any deposit agreement may be terminated by us upon not less than 30 days'
prior written notice to the applicable depositary if a majority of each series
of preferred stock affected by the termination consents to the termination. When
that event occurs, the depositary will be required to deliver or make available
to each holder of depositary shares, upon surrender of the depositary receipts
held by the holder, the number of whole or fractional shares of preferred stock
as are represented by the depositary shares evidenced by the depositary
receipts, together with any other property held by the depositary with respect
to the depositary shares. In addition, a deposit agreement will automatically
terminate if:

    - all outstanding depositary shares have been redeemed;

    - there shall have been a final distribution in respect of the related
      preferred stock in connection with our liquidation and the distribution
      has been made to the holders of depositary receipts evidencing the
      depositary shares underlying the preferred stock; or

                                      -20-
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    - each of the shares of related preferred stock shall have been converted or
      exchanged into securities not represented by depositary shares.

CHARGES OF A DEPOSITARY

    We will pay all transfer and other taxes and governmental charges arising
solely from the existence of a deposit agreement. In addition, we will pay the
fees and expenses of a depositary in connection with the initial deposit of the
preferred stock and any redemption of the preferred stock. However, holders of
depositary shares will pay any transfer taxes or other governmental charges and
the fees and expenses of a depositary, including a fee for the withdrawal of
shares of preferred stock upon surrender of depositary receipts, as are
expressly provided in the deposit agreement to be for their accounts.

RESIGNATION AND REMOVAL OF DEPOSITARY

    A depositary may resign at any time by delivering to us notice of its
election to do so. In addition, we may at any time remove a depositary. Any
resignation or removal will take effect when we appoint a successor depositary
and it accepts the appointment. We must appoint a successor depositary within
60 days after delivery of the notice of resignation or removal. A depositary
must be a bank or trust company having its principal office in the United States
that has a combined capital and surplus of at least $50 million.

MISCELLANEOUS

    A depositary will be required to forward to holders of depositary shares any
reports and communications that it receives from us with respect to the related
preferred stock. Holders of depository shares will be able to inspect the
transfer books of the depository and the list of holders of depositary shares
upon reasonable notice.

    Neither we nor a depositary will be liable if either of us are prevented
from, or delayed in performing, by law or any circumstances beyond our control,
our obligations under a deposit agreement. Our obligations and those of the
depositary under a deposit agreement will be limited to performing our duties in
good faith and without gross negligence or willful misconduct. Neither we nor
any depositary will be obligated to prosecute or defend any legal proceeding in
respect of any depositary receipts, depositary shares or related preferred stock
unless satisfactory indemnity is furnished. We and each depositary will be
permitted to rely on written advice of counsel or accountants, on information
provided by persons presenting preferred stock for deposit, by holders of
depositary shares, or by other persons believed in good faith to be competent to
give the information, and on documents believed in good faith to be genuine and
signed by a proper party.

    If a depositary receives conflicting claims, requests or instructions from
any holders of depositary shares, on the one hand, and us, on the other hand,
the depositary shall be entitled to act on the claims, requests or instructions
received from us.

                          DESCRIPTION OF OUR WARRANTS

    This section describes the general terms and provisions of our warrants to
acquire our securities that we may issue from time to time. The applicable
prospectus supplement will describe the specific terms of the warrants offered
through that prospectus supplement.

    We may issue, together with any other securities being offered or
separately, warrants entitling the holder to purchase from or sell to us, or to
receive from us the cash value of the right to purchase or sell, our debt
securities, preferred stock, depositary shares or common stock. We and a warrant
agent will enter a warrant agreement pursuant to which the warrants will be
issued. The warrant agent will act solely as our agent in connection with the
warrants and will not assume any obligation or

                                      -21-
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relationship of agency or trust for or with any holders or beneficial owners of
warrants. We will file a copy of the warrants and the warrant agreement with the
SEC at or before the time of the offering of the applicable series of warrants.
A holder of our warrants should refer to the provisions of the applicable
warrant agreement and prospectus supplement for more specific information.

    In the case of each series of warrants, the applicable prospectus supplement
will describe the terms of the warrants being offered thereby. These include the
following, if applicable:

    - the offering price;

    - the number of warrants offered;

    - the securities underlying the warrants;

    - the exercise price, the amount of securities you will receive upon
      exercise, the procedure for exercise of the warrants and the
      circumstances, if any, that will cause the warrants to be automatically
      exercised;

    - the rights, if any, we have to redeem the warrants;

    - the date on which the warrants will expire;

    - U.S. federal income tax consequences;

    - the name of the warrant agent; and

    - any other terms of the warrants.

    Warrants may be exercised at the appropriate office of the warrant agent or
any other office indicated in the applicable prospectus supplement. Before the
exercise of warrants, holders will not have any of the rights of holders of the
securities purchasable upon exercise and will not be entitled to payments made
to holders of those securities.

    The warrant agreements may be amended or supplemented without the consent of
the holders of the warrants to which it applies to effect changes that are not
inconsistent with the provisions of the warrants and that do not materially and
adversely affect the interests of the holders of the warrants. However, any
amendment that materially and adversely alters the rights of the holders of
warrants will not be effective unless the holders of at least a majority of the
applicable warrants then outstanding approve the amendment. Every holder of an
outstanding warrant at the time any amendment becomes effective, by continuing
to hold the warrant, will be bound by the applicable warrant agreement as
amended. The prospectus supplement applicable to a particular series of warrants
may provide that certain provisions of the warrants, including the securities
for which they may be exercisable, the exercise price and the expiration date,
may not be altered without the consent of the holder of each warrant.

    DESCRIPTION OF THE STOCK PURCHASE CONTRACTS AND THE STOCK PURCHASE UNITS

    We may issue contracts obligating holders to purchase from us, and us to
sell to the holders, a specified number of shares of common stock at a future
date or dates, which we refer to herein as "stock purchase contracts." The price
per share of common stock and the number of shares of common stock may be fixed
at the time the stock purchase contracts are issued or may be determined by
reference to a specific formula set forth in the stock purchase contracts. The
stock purchase contracts may be issued separately or as part of units consisting
of a stock purchase contract and debt securities, trust preferred securities or
debt obligations of third parties, including U.S. treasury securities, which
secure the holders' obligations to purchase the common stock under the stock
purchase contracts. We refer to these units herein as "stock purchase units."
The stock purchase contracts may require holders to secure their obligations
thereunder in a specified manner. The stock purchase contracts also may

                                      -22-
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require us to make periodic payments to the holders of the stock purchase units
or vice versa, and such payments may be unsecured or refunded on some basis.

    The applicable prospectus supplement will describe the terms of the stock
purchase contracts or stock purchase units. The description in the applicable
prospectus supplement will not necessarily be complete, and reference will be
made to the stock purchase contracts, and, if applicable, collateral or
depositary arrangements, relating to the stock purchase contracts or stock
purchase units. Material U.S. federal income tax considerations applicable to
the stock purchase units and the stock purchase contracts will also be discussed
in the applicable prospectus supplement.

                 DESCRIPTION OF THE TRUST PREFERRED SECURITIES

    If and when IM Capital Trust issues trust preferred securities, its
declaration of trust will be replaced by an amended and restated declaration of
trust which will authorize its trustees to issue one series of trust preferred
securities and one series of trust common securities. The form of amended and
restated declaration of trust is filed with the SEC as an exhibit to the
registration statement of which this prospectus is a part.

    The terms of the trust preferred securities will include those stated in IM
Capital Trust's declaration of trust, as it may be amended and restated from
time to time, and those made a part of that declaration by the Trust Indenture
Act of 1939. This section describes the general terms and provisions of IM
Capital Trust's amended and restated declaration of trust and the trust
securities IM Capital Trust may offer from time to time. The applicable
prospectus supplement will describe the specific terms of the amended and
restated declaration of trust and the trust preferred securities offered through
that prospectus supplement. Any final amended and restated declaration of trust
will be filed with the SEC if IM Capital Trust issues trust preferred
securities. A holder of trust preferred securities should read the applicable
prospectus supplement and the amended and restated declaration of trust for more
specific information.

    The prospectus supplement relating to the trust preferred securities being
offered will include specific terms relating to the offering. These terms will
include some or all of the following:

    - the designation of the trust preferred securities;

    - the number of trust preferred securities to be issued;

    - the annual distribution rate and any conditions upon which distributions
      are payable, the distribution payment dates, the record dates for
      distribution payments and the additional amounts, if any, that may be
      payable with respect to the trust preferred securities;

    - whether distributions will be cumulative and compounding and, if so, the
      dates from which distributions will be cumulative or compounded;

    - the amounts that will be paid out of the assets of IM Capital Trust, after
      the satisfaction of liabilities to creditors of IM Capital Trust, to the
      holders of trust preferred securities upon dissolution, winding up or
      termination of IM Capital Trust;

    - any repurchase, redemption or exchange provisions;

    - any preference or subordination rights upon a default or liquidation of IM
      Capital Trust;

    - any voting rights of the trust preferred securities in addition to those
      required by law, including the number of votes per trust preferred
      security and any requirement for the approval by the holders of trust
      preferred securities, as a condition to a specified action or amendments
      to the declaration of trust;

                                      -23-
<Page>
    - terms for any conversion or exchange of the related series of our debt
      securities or the trust preferred securities into other securities;

    - any rights to defer distributions on the trust preferred securities by
      extending the interest payment period on the related series of our debt
      securities;

    - any terms and conditions upon which the related series of our debt
      securities may be distributed to holders of trust preferred securities;
      and

    - any other relevant terms, rights, preferences, privileges, limitations or
      restrictions of the trust preferred securities.

    The regular trustee, on behalf of IM Capital Trust and pursuant to the
declaration of trust, will issue one class of trust preferred securities and one
class of trust common securities. The trust preferred and trust common
securities will represent undivided beneficial ownership interests in the assets
of IM Capital Trust. Except as described in the applicable prospectus
supplement, the trust preferred securities will rank equally, and payments will
be made thereon proportionately, with the trust common securities. The trust
preferred securities will be issued to the public under the registration
statement of which this prospectus is a part. The trust common securities will
be issued directly or indirectly to us.

    The only source of cash to make payments on the trust preferred securities
issuable by IM Capital Trust will be payments on debt securities IM Capital
Trust purchases from us. The property trustee of IM Capital Trust will hold
legal title to the debt securities IM Capital Trust purchases in trust for the
benefit of the holders of its trust preferred securities. If IM Capital Trust is
dissolved, after satisfaction of IM Capital Trust's creditors, the property
trustee may distribute the debt securities held in trust on a proportionate
basis to the holders of trust preferred and trust common securities.

    We will execute a guarantee agreement for the benefit of the holders of the
trust preferred securities. The terms of our guarantee will be set forth in the
applicable prospectus supplement and are summarized under the caption
"Description of the Trust Preferred Securities Guarantee" included elsewhere in
this prospectus. The guarantee will not guarantee the payment of distributions,
as defined below, or any amounts payable on redemption or liquidation of the
trust preferred securities when IM Capital Trust does not have funds available
to make these payments.

    In the applicable prospectus supplement we will also describe certain
material U.S. federal income tax consequences and special considerations
applicable to the trust preferred securities.

            DESCRIPTION OF THE TRUST PREFERRED SECURITIES GUARANTEE

    If and when IM Capital Trust issues trust preferred securities, we will
fully and unconditionally guarantee payments on the trust preferred securities
as described in this section, any applicable prospectus supplement and the
guarantee executed by us in connection with the issuance of the trust preferred
securities. The Bank of New York, as guarantee trustee, will hold the guarantee
for the benefit of the holders of trust preferred securities.

    This section describes the general terms and provisions of our trust
preferred securities guarantee. The applicable prospectus supplement will
describe the specific terms of the trust preferred securities guarantee. The
form of trust guarantee is filed with the SEC as an exhibit to the registration
statement of which this prospectus is a part. We will file with the SEC a final
guarantee if IM Capital Trust issues trust preferred securities. A holder of
trust preferred securities should refer to the applicable prospectus supplement
and to the full text of our guarantee and those terms made a part of the
guarantee by the Trust Indenture Act of 1939 for more specific information.

                                      -24-
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    We will irrevocably and unconditionally agree to pay in full to holders of
trust preferred securities the following amounts to the extent not paid by IM
Capital Trust:

    - any accumulated and unpaid distributions and any additional amounts with
      respect to the trust preferred securities and any redemption price for
      trust preferred securities called for redemption by IM Capital Trust, if
      and to the extent that we have made corresponding payments on the debt
      securities to the property trustee of IM Capital Trust; and

    - payments upon the dissolution of IM Capital Trust equal to the lesser of:

     (1) the liquidation amount plus all accumulated and unpaid distributions
        and additional amounts on the trust preferred securities to the extent
        IM Capital Trust has funds legally available for those payments; and

     (2) the amount of assets of IM Capital Trust remaining legally available
        for distribution to the holders of trust preferred securities in
        liquidation of IM Capital Trust.

    We will not be required to make these liquidation payments if:

    - IM Capital Trust distributes the debt securities to the holders of trust
      preferred securities in exchange for their trust preferred securities; or

    - IM Capital Trust redeems the trust preferred securities in full upon the
      maturity or redemption of the debt securities.

    We may satisfy our obligation to make a guarantee payment either by making
payment directly to the holders of trust preferred securities or to the
guarantee trustee for remittance to the holders or by causing IM Capital Trust
to make the payment to them.

    The guarantee is a guarantee from the time of issuance of the applicable
series of trust preferred securities. THE GUARANTEE ONLY COVERS, HOWEVER,
DISTRIBUTIONS AND OTHER PAYMENTS ON TRUST PREFERRED SECURITIES IF AND TO THE
EXTENT THAT WE HAVE MADE CORRESPONDING PAYMENTS ON THE DEBT SECURITIES TO THE
APPLICABLE PROPERTY TRUSTEE. IF WE DO NOT MAKE THOSE CORRESPONDING PAYMENTS ON
THE DEBT SECURITIES, IM CAPITAL TRUST WILL NOT HAVE FUNDS AVAILABLE FOR PAYMENTS
AND WE WILL HAVE NO OBLIGATION TO MAKE A GUARANTEE PAYMENT.

    The obligations under the debt securities, the associated indenture, IM
Capital Trust's declaration of trust and our related guarantee, taken together,
will provide a full and unconditional guarantee of payments of distributions and
other amounts due on the trust preferred securities.

IRON MOUNTAIN COVENANTS

    In the guarantee, we will agree that, as long as any trust preferred
securities issued by IM Capital Trust are outstanding, we will not make the
payments and distributions described below if:

    - we are in default on our guarantee payments or other payment obligations
      under the related guarantee;

    - any trust enforcement event under IM Capital Trust's declaration of trust
      has occurred and is continuing; or

    - we elect to defer payments of interest on the related debt securities by
      extending the interest payment period, and that deferral period is
      continuing.

                                      -25-
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    In these circumstances, we will agree that we will not:

    - declare or pay any dividends or distributions on, or redeem, purchase,
      acquire, or make a liquidation payment with respect to, any of our capital
      stock; or

    - make any payment of principal, interest or premium, if any, on or repay,
      repurchase or redeem any debt securities that rank equally with, or junior
      in interest to, the debt securities we issue to IM Capital Trust or make
      any guarantee payments with respect to any guarantee by us of the debt of
      any of our subsidiaries if that guarantee ranks equally with or junior in
      interest to the debt securities we issue to IM Capital Trust.

    However, even during these circumstances, we may:

    - purchase or acquire our capital stock in connection with the satisfaction
      of our obligations under any employee benefit plans or pursuant to any
      contract or security outstanding on the first day of any extension period
      requiring us to purchase our capital stock (other than a contract or
      security ranking expressly by its terms on a parity with or junior to the
      debt securities);

    - reclassify our capital stock or exchange or convert one class or series of
      our capital stock for another class or series of our capital stock;

    - purchase fractional interests in shares of our capital stock pursuant to
      the conversion or exchange provisions of our capital stock or the security
      being converted or exchanged;

    - declare dividends or distributions in our capital stock where the dividend
      stock is the same stock as that on which the dividend is being paid;

    - redeem, repurchase or issue any rights pursuant to a rights agreement; and

    - make payments under the guarantee related to the trust preferred
      securities.

    In addition, as long as trust preferred securities issued by IM Capital
Trust are outstanding, we will agree that we will:

    - remain the sole direct or indirect owner of all the outstanding trust
      common securities of IM Capital Trust, except as permitted by its
      declaration of trust;

    - permit the trust common securities of IM Capital Trust to be transferred
      only as permitted by its declaration of trust; and

    - use reasonable efforts to cause IM Capital Trust to continue to be treated
      as a grantor trust for U.S. federal income tax purposes, except in
      connection with a distribution of debt securities to the holders of trust
      preferred securities as provided in its declaration of trust, in which
      case IM Capital Trust would be dissolved.

AMENDMENTS AND ASSIGNMENT

    We and the guarantee trustee may amend the guarantee without the consent of
any holder of trust preferred securities if the amendment does not adversely
affect the rights of the holders in any material respect. In all other cases, we
and the guarantee trustee may amend the guarantee only with the prior approval
of the holders of at least a majority of outstanding trust preferred securities
issued by IM Capital Trust.

    We may assign our obligations under the guarantee only in connection with a
consolidation, merger or asset sale involving us that is permitted under the
indenture governing the debt securities.

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TERMINATION OF THE GUARANTEE

    Our guarantee will terminate upon:

    - full payment of the redemption price of all trust preferred securities of
      IM Capital Trust;

    - distribution of the related debt securities, or any securities into which
      those debt securities are convertible, to the holders of the trust
      preferred and trust common securities of IM Capital Trust in exchange for
      all the securities issued by IM Capital Trust; or

    - full payment of the amounts payable upon liquidation of IM Capital Trust.

    The guarantee will, however, continue to be effective, or will be
reinstated, if any holder of trust preferred securities must repay any amounts
paid on those trust preferred securities or under the guarantee.

STATUS OF THE GUARANTEE

    We will specify in the applicable prospectus supplement the ranking of the
guarantee with respect to our capital stock and other liabilities, including
other guarantees.

    The guarantee will be deposited with the guarantee trustee to be held for
the benefit of the holders of the trust preferred securities. The guarantee
trustee will have the right to enforce the guarantee on the holders' behalf. In
most cases, the holders of a majority of outstanding trust preferred securities
issued by IM Capital Trust will have the right to direct the time, method and
place of:

    - conducting any proceeding for any remedy available to the applicable
      guarantee trustee; or

    - exercising any trust or other power conferred upon that guarantee trustee
      under the guarantee.

    The guarantee will constitute a guarantee of payment and not merely of
collection. This means that the guarantee trustee may institute a legal
proceeding directly against us to enforce the payment rights under the
guarantee, without first instituting a legal proceeding against IM Capital Trust
or any other person or entity.

    If the guarantee trustee fails to enforce the guarantee or we fail to make a
guarantee payment, a holder of the trust preferred securities may institute a
legal proceeding directly against us to enforce the holder's rights under that
guarantee without first instituting a legal proceeding against IM Capital Trust,
the guarantee trustee or any other person or entity.

PERIODIC REPORTS UNDER GUARANTEE

    We will be required to provide annually to the guarantee trustee a statement
as to our performance of our obligations and our compliance with all conditions
under the guarantee.

DUTIES OF GUARANTEE TRUSTEE

    The guarantee trustee normally will perform only those duties specifically
set forth in the guarantee. The guarantee will not contain any implied
covenants. If a default occurs on the guarantee, the guarantee trustee will be
required to use the same degree of care and skill in the exercise of its powers
under the guarantee as a prudent person would exercise or use under the
circumstances in the conduct of his own affairs. The guarantee trustee will
exercise any of its rights or powers under the guarantee at the request or
direction of holders of the trust preferred securities only if the guarantee
trustee is offered security and indemnity satisfactory to it.

                                      -27-
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 RELATIONSHIP AMONG THE DEBT SECURITIES, THE TRUST PREFERRED SECURITIES AND THE
                      TRUST PREFERRED SECURITIES GUARANTEE

    To the extent set forth in the guarantee and to the extent funds are
available, we will irrevocably guarantee the payment of distributions and other
amounts due on the trust preferred securities. If and to the extent we do not
make payments on the debt securities to the property trustee, IM Capital Trust
will not have sufficient funds to pay distributions or other amounts due on the
trust preferred securities. The guarantee does not cover any payment of
distributions or other amounts due on the trust preferred securities unless IM
Capital Trust has sufficient funds for the payment of such distributions or
other amounts. In such event, a holder of trust preferred securities may
institute a legal proceeding directly against us to enforce payment of such
distributions or other amounts to such holder after the respective due dates.
Taken together, our obligations under the debt securities, the associated
indenture, IM Capital Trust's declaration of trust and our related guarantee
will provide a full and unconditional guarantee of payments of distributions and
other amounts due on the trust preferred securities. No single document standing
alone or operating in conjunction with fewer than all of the other documents
constitutes such guarantee. It is only the combined operation of these documents
that provides a full and unconditional guarantee of IM Capital Trust's payment
obligations under the trust preferred securities.

SUFFICIENCY OF PAYMENTS

    As long as payments of interest and other amounts are made when due on the
debt securities, such payments will be sufficient to cover distributions and
payments due on the trust preferred securities because of the following factors:

    - the aggregate principal amount of the debt securities will be equal to the
      sum of the aggregate stated liquidation amount of the trust preferred
      securities;

    - the interest rate and the interest and other payment dates on the debt
      securities will match the distribution rate and distribution and other
      payment dates for the trust preferred securities;

    - we, as issuer of the debt securities, will pay, and IM Capital Trust will
      not be obligated to pay, directly or indirectly, any costs, expenses,
      debts and obligations of IM Capital Trust, other than with respect to the
      trust preferred securities; and

    - the declaration of trust will further provide that IM Capital Trust will
      not engage in any activity that is not consistent with the limited
      purposes of IM Capital Trust.

    Notwithstanding anything to the contrary in the indenture, we have the right
to set off any payment we are otherwise required to make thereunder against and
to the extent we have already made, or are concurrently on the date of such
payment making, a related payment under the guarantee.

ENFORCEMENT RIGHTS OF HOLDERS OF PREFERRED SECURITIES

    The declaration of trust provides that if we fail to make interest or other
payments on the debt securities when due, taking account of any extension
period, the holders of the trust preferred securities may direct the property
trustee to enforce its rights under the applicable indenture. If the property
trustee fails to enforce its rights under the indenture in respect of an event
of default under the indenture, any holder of record of trust preferred
securities may, to the fullest extent permitted by applicable law, institute a
legal proceeding against us to enforce the property trustee's rights under the
indenture without first instituting any legal proceeding against IM Capital
Trust, the property trustee or any other person or entity. Notwithstanding the
foregoing, if a trust enforcement event has occurred and is continuing and such
event is attributable to our failure to pay interest, premium or principal on
the debt securities on the date such interest, premium or principal is otherwise
payable, then a holder

                                      -28-
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of trust preferred securities may institute a direct action against us for
payment of such holder's pro rata share. If a holder brings such a direct
action, we will be entitled to that holder's rights under IM Capital Trust's
declaration of trust to the extent of any payment made by us to that holder.

    If we fail to make payments under the guarantee, a holder of trust preferred
securities may institute a proceeding directly against us for enforcement of the
guarantee for such payments.

LIMITED PURPOSE OF TRUST

    The trust preferred securities evidence undivided beneficial ownership
interests in the assets of IM Capital Trust, and IM Capital Trust exists for the
sole purpose of issuing and selling the trust preferred and trust common
securities and using the proceeds to purchase our debt securities. A principal
difference between the rights of a holder of trust preferred securities and a
holder of our debt securities is that a holder of our debt securities is
entitled to receive from us the principal amount of, and interest accrued on,
the debt securities held, while a holder of trust preferred securities is
entitled to receive distributions and other payments from IM Capital Trust, or
from us under the guarantee, only if, and to the extent, IM Capital Trust has
funds available for the payment of such distributions and other payments.

RIGHTS UPON DISSOLUTION

    Upon any voluntary or involuntary dissolution of IM Capital Trust involving
the redemption or repayment of the debt securities, the holders of the trust
preferred securities will be entitled to receive, out of assets held by IM
Capital Trust, subject to the rights of creditors of IM Capital Trust, if any,
the liquidation distribution in cash. Because we are the guarantor under the
guarantee and, as issuer of the debt securities, we have agreed to pay for all
costs, expenses and liabilities of IM Capital Trust other than IM Capital
Trust's obligations to the holders of the trust preferred securities, the
positions of a holder of trust preferred securities and a holder of debt
securities relative to other creditors and to our stockholders in the event of
liquidation or bankruptcy of us would be substantially the same.

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   DESCRIPTION OF CERTAIN PROVISIONS OF PENNSYLVANIA LAW AND OUR ARTICLES OF
                            INCORPORATION AND BYLAWS

    We are organized as a Pennsylvania corporation. The following is a summary
of our articles of incorporation and by-laws and certain provisions of
Pennsylvania law. Because it is a summary, it does not contain all the
information that may be important to you. If you want more information, you
should read our entire articles of incorporation and by-laws, copies of which we
have previously filed with the SEC, see "Where You Can Find More Information,"
or refer to the provisions of Pennsylvania law.

    Pennsylvania law, our articles of incorporation and our bylaws contain some
provisions that could delay or make more difficult the acquisition of us by
means of a tender offer, a proxy contest or otherwise. These provisions, as
described below, are expected to discourage certain types of coercive takeover
practices and inadequate takeover bids and to encourage persons seeking to
acquire control of us first to negotiate with us. We believe that the benefits
of increased protection of our ability to negotiate with the proponent of an
unfriendly or unsolicited proposal to acquire or restructure us outweigh the
disadvantages of discouraging such proposals because, among other things,
negotiations with respect to such proposals could result in an improvement of
their terms.

PENNSYLVANIA ANTI-TAKEOVER STATUTORY PROVISIONS

    We are subject to the anti-takeover provisions of Section 2538 and Sections
2551-2556 of the Pennsylvania Business Corporation Law of 1988, as amended (the
"PBCL"), which in certain cases impose restrictions on, including providing for
supermajority shareholder approval of, business combinations involving us and
any "interested shareholder." "Interested shareholder" includes generally, in
the case of Section 2538, shareholders who are a party to the business
combination or who are treated differently from other shareholders, and, in the
case of Sections 2551-2556, shareholders beneficially owning 20% or more of the
voting power of a "registered" corporation, such as us, or an affiliate or
associate of such corporation which, during the prior five year period,
beneficially owned 20% or more of the voting power of such corporation. The term
"business combination" is broadly defined to include various transactions
including mergers, consolidations, asset sales and other similar transactions.
The PBCL provides for further statutory anti-takeover provisions relating to
control transactions, control-share acquisitions and disgorgement. We have
specifically opted out of these provisions pursuant to our articles of
incorporation.

    The PBCL also provides that when making decisions concerning takeovers or
any other matters, the directors of a corporation may consider, to the extent
that they deem appropriate, among other things, (1) the effects of any proposed
transaction upon any or all groups affected by the transaction, including, among
others, shareholders, employees, suppliers, customers, creditors and communities
in which we have offices, (2) the short-term and long-term interests of the
corporation and (3) the resources, intent and conduct of the person seeking
control.

CLASSIFIED BOARD OF DIRECTORS AND OTHER PROVISIONS OF OUR ARTICLES OF
  INCORPORATION AND BYLAWS

    Our bylaws provide that, other than directors to be elected by holders of
any series of preferred stock, our board of directors is to be composed of three
classes, with staggered three-year terms, each class to be as nearly equal in
number as reasonably possible. Accordingly, at each annual meeting of
shareholders, only approximately one-third of the directors will be elected. The
classification of directors has the effect of making it more difficult to change
the composition of our board of directors.

    Our bylaws provide that a vacancy on the board of directors, including a
vacancy created by an increase in the size of the board of directors by the
directors, may be filled by a majority of the remaining directors, or by a sole
remaining director, or by the shareholders, and each person so elected shall be
a director to serve for the balance of the unexpired term of that class of
directors. Likewise,

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under the PBCL, without an unanimous vote, shareholders may only remove
directors for cause. These provisions are to ensure that a third party would be
precluded from removing incumbent directors and simultaneously gaining control
of the board of directors by filling the vacancies with its own nominees.

    Certain other provisions of our articles of incorporation and bylaws could
also have the effect of preventing or delaying any change in control of us,
including:

    - the advance notification procedures imposed on shareholders for
      shareholder nominations of candidates for the board of directors and for
      other shareholder business to be conducted at annual or special meetings;

    - the absence of authority for shareholders to call special shareholder
      meetings, except in certain limited circumstances mandated by the PBCL;
      and

    - the absence of authority for shareholder action by unanimous or partial
      written consent in lieu of an annual or special meeting.

    These provisions, the classified board of directors and statutory
anti-takeover provisions, could make it more difficult for a third party to
acquire, or discourage a third party from seeking to acquire, control of us.

LIMITATION OF DIRECTORS' LIABILITY AND INDEMNIFICATION OF DIRECTORS AND OFFICERS

    As permitted by the PBCL, our bylaws provide that a director shall not be
personally liable for monetary damages for any action taken, or any failure to
take any action, unless the director breaches or fails to perform the duties of
his office under the PBCL, and the breach or failure to perform constitutes
self-dealing, willful misconduct or recklessness. These provisions of our
bylaws, however, do not apply to the responsibility or liability of a director
pursuant to any criminal statute, or to the liability of a director for the
payment of our taxes pursuant to local, Pennsylvania or federal law. These
provisions offer persons who serve on the board of directors protection against
awards of monetary damages for negligence in the performance of their duties.

    Our bylaws also provide that directors or officers made a party to, or
threatened to be made a party to, or otherwise involved in, any proceeding,
because he or she is or was a representative of us or is or was serving as a
representative of another corporation or any partnership, joint venture, trust,
employee benefit plan or other enterprise, on our behalf, shall be indemnified
and held harmless by us to the fullest extent permitted by Pennsylvania law
against all expenses, liabilities and losses reasonably incurred by or imposed
upon him or her, in connection with any threatened, pending or completed action,
suit or proceeding. Indemnification is not available, however, if a court
determines that the act or failure to act giving rise to the claim constitutes
willful misconduct or recklessness.

    Pursuant to our bylaws, amending the provisions to reduce the limitation of
director's liability or limit the right to indemnification requires unanimous
vote of the directors or a majority vote of the shareholders.

                              PLAN OF DISTRIBUTION

    We and IM Capital Trust may sell the offered securities to one or more
underwriters for public offering and sale by them. We and IM Capital Trust may
also sell the offered securities to investors directly or through agents. We
will name any underwriter or agent involved in the offer and sale of the offered
securities in the applicable prospectus supplement.

    The distribution of offered securities may be effected from time to time in
one or more transactions at:

    - a fixed price or varying prices;

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    - market prices prevailing at the time of sale;

    - prices related to the market prices; or

    - negotiated prices.

    In compliance with NASD guidelines, the maximum commission or discount to be
received by any NASD member or independent broker dealer may not exceed 8% of
the aggregate amount of the securities offered pursuant to this prospectus or
any applicable prospectus supplement.

    Underwriters, dealers and agents participating in the distribution of the
securities may be deemed to be underwriters, and any discounts and commissions
received by them and any profit realized by them on resale of the securities may
be deemed to be underwriting discounts and commissions under the Securities Act
of 1933. Underwriters, dealers and agents may be entitled, under agreements with
us and/or IM Capital Trust, to indemnification against and contribution toward
certain civil liabilities, including liabilities under the Securities Act of
1933, and to reimbursement by us and/or IM Capital Trust for certain expenses.

    If an underwriter or underwriters are used in the offer or sale of
securities, we and/or IM Capital Trust will execute an underwriting agreement
with the underwriters at the time of sale of the securities to the underwriters,
and the names of the underwriters and the principal terms of our and/or IM
Capital Trust's agreements with the underwriters will be provided in the
applicable prospectus supplement.

    If we so indicate in the prospectus supplement, we and IM Capital Trust may
authorize agents, underwriters or dealers to solicit offers from certain types
of institutions to purchase securities from us or IM Capital Trust at the public
offering price under delayed delivery contracts. These contracts would provide
for payment and delivery on a specified date in the future. The contracts would
be subject only to those conditions described in the prospectus supplement. The
prospectus supplement will describe the commission payable for solicitation of
those contracts.

    Unless otherwise specified in the related prospectus supplement, each series
of offered securities, other than shares of common stock, will be a new issue
with no established trading market. Any shares of common stock sold pursuant to
a prospectus supplement will be listed on the New York Stock Exchange, subject
to official notice of issuance. We and IM Capital Trust may elect to list any
other series or class of offered securities on an exchange or on the Nasdaq
National Market, but are not obligated to do so. Any underwriters to whom
offered securities are sold by us for public offering and sale may make a market
in those offered securities. Underwriters will not be obligated to make any
market, however, and may discontinue any market making at any time without
notice. No assurance can be given as to the liquidity of, or the trading markets
for, any offered securities.

    Certain of the underwriters and their affiliates may engage in transactions
with and perform services for us in the ordinary course of business for which
they receive compensation.

    The specific terms and manner of sale of the offered securities will be
shown or summarized in the applicable prospectus supplement.

                       VALIDITY OF THE OFFERED SECURITIES

    Sullivan & Worcester LLP, Boston, Massachusetts, will pass upon the validity
of the debt securities, preferred stock, depositary shares, common stock,
warrants, guarantees, stock purchase contracts and stock purchase units. As to
certain matters of Pennsylvania law, Sullivan & Worcester LLP will rely upon an
opinion of Ballard Spahr Andrews & Ingersoll, LLP, Philadelphia, Pennsylvania.
Jas. Murray Howe is of counsel to Sullivan & Worcester LLP and beneficially owns
45,000 shares of common stock.

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    The validity of the trust preferred securities to be issued by IM Capital
Trust, and the enforceability of its declaration of trust and the creation of IM
Capital Trust, will be passed upon by Richards, Layton and Finger, P.A.,
Wilmington, Delaware.

                                    EXPERTS

    The consolidated financial statements of Iron Mountain Incorporated and its
subsidiaries for the three years ended December 31, 2000, and its supplemental
schedule, Valuation and Qualifying Accounts, included in its Annual Report on
Form 10-K for the year ended December 31, 2000, dated March 23, 2001 and
incorporated by reference into this registration statement, have been audited by
Arthur Andersen LLP, independent public accountants, as set forth in their
reports. In their report on Iron Mountain's consolidated financial statements,
that firm states that, with respect to certain subsidiaries, its opinion is
based on the report of RSM Robson Rhodes, independent public accountants. The
consolidated financial statements and supporting schedule referred to above have
been incorporated by reference herein in reliance upon the authority of those
two firms as experts in giving said reports.

    The consolidated financial statements of Iron Mountain Incorporated (f/k/a
Pierce Leahy Corp.), and its subsidiaries for the three years ended
December 31, 1999, and its supplemental schedule, Valuation and Qualifying
Accounts, included in its Annual Report on Form 10-K for the year ended
December 31, 1999, dated March 30, 2000, have been audited by Arthur Andersen
LLP, independent public accountants, as indicated in their reports with respect
thereto, and are incorporated by reference herein in reliance upon the authority
of said firm as experts in giving said reports.

    The financial statements of Data Base, Inc. and Affiliate for the three
years ended December 31, 1998, included in Iron Mountain's Current Report on
Form 8-K dated April 16, 1999, have been audited by Moss Adams LLP, independent
public accountants, as indicated in their report with respect thereto, and are
incorporated by reference herein in reliance upon the authority of said firm as
experts in giving said report.

    The financial statements of Data Storage Center, Inc. as of December 31,
1998 and 1999, and for the years then ended, included in Iron Mountain
Incorporated's Current Report on Form 8-K dated May 15, 2000, have been audited
by Deloitte & Touche LLP, independent auditors, as stated in their report, which
is incorporated herein by reference, and have been so incorporated in reliance
upon the report of such firm given upon their authority as experts in accounting
and auditing.

                      WHERE YOU CAN FIND MORE INFORMATION

    We file annual, quarterly and current reports, proxy statements and other
information with the SEC. You may read and copy any reports, statements or other
information on file at the SEC's public reference room at 450 Fifth Street,
N.W., Washington, D.C. 20549. You can request copies of those documents upon
payment of a duplicating fee to the SEC. Please call the SEC at 1-800-SEC-0330
for further information on the operation of the public reference rooms. You can
review our SEC filings and the registration statement by accessing the SEC's
Internet site at http://www.sec.gov. Our common stock is listed on the New York
Stock Exchange where reports, proxy statements and other information concerning
us can also be inspected. The offices of the NYSE are located at 20 Broad
Street, New York, New York 10005.

                      DOCUMENTS INCORPORATED BY REFERENCE

    The SEC allows us to "incorporate by reference" the information we file with
them, which means that we can disclose important information to you by referring
you to those documents. The information incorporated by reference is considered
to be part of this prospectus. Statements in this prospectus regarding the
contents of any contract or other document may not be complete. You should

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refer to the copy of the contract or other document filed as an exhibit to the
registration statement. Later information filed with the SEC will update and
supersede information we have included or incorporated by reference in this
prospectus.

    We incorporate by reference the following documents filed by us:

    - Annual Report on Form 10-K for the fiscal year ended December 31, 2000.

    - Quarterly Reports on Form 10-Q for the quarters ended March 31, June 30
      and September 30, 2001.

    - Current Reports on Form 8-K filed March 23, 2001, April 3, 2001,
      September 7, 2001, September 17, 2001 and December 13, 2001.

    - The description of our common stock contained in the Registration
      Statement on Form 8-A dated May 27, 1997, including all amendments and
      reports filed for the purpose of updating such description.

    In addition to the documents listed above, we incorporate by reference any
future filings made by us, including filings made prior to the effectiveness of
this registration statement, with the SEC under Section 13(a), 13(c), 14 or
15(d) of the Securities Exchange Act of 1934 until our offering of the
securities made by this prospectus is completed or terminated.

    We will provide you with a copy of the information we have incorporated by
reference, excluding exhibits other than those to which we specifically refer.
You may obtain this information at no cost by writing or telephoning us at: 745
Atlantic Avenue, Boston, Massachusetts 02111, (617) 535-4799, Attention:
Investor Relations.

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