<PAGE>   1
                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    FORM 10-Q


[X]    QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
       EXCHANGE ACT OF 1934 FOR THE QUARTERLY PERIOD ENDED JUNE 30, 1998

                                       OR

[ ]    TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES
       EXCHANGE ACT OF 1934 FOR THE TRANSITION PERIOD FROM ____________ TO
       ____________


                         Commission file number 0-21518

                            IEA INCOME FUND XII, L.P.
             (Exact name of registrant as specified in its charter)


               California                                    94-3143940
    (State or other jurisdiction of                       (I.R.S. Employer
     incorporation or organization)                      Identification No.)

    444 Market Street, 15th Floor, San Francisco, California    94111
    (Address of principal executive offices)                  (Zip Code)

                                 (415) 677-8990
              (Registrant's telephone number, including area code)


Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the preceding 12 months (or for such shorter period that the registrant was
required to file such reports), and (2) has been subject to such filing
requirements for the past 90 days. Yes   X  . No .
                                       ----     ----

<PAGE>   2

                            IEA INCOME FUND XII, L.P.

                  REPORT ON FORM 10-Q FOR THE QUARTERLY PERIOD
                               ENDED JUNE 30, 1998

                                TABLE OF CONTENTS


<TABLE>
<CAPTION>
                                                                                                                     PAGE
<S>        <C>                                                                                                       <C>
PART I - FINANCIAL INFORMATION

  Item 1.  Financial Statements

           Balance Sheets - June 30, 1998 (unaudited) and December 31, 1997                                             4

           Statements of Operations for the three and six months ended June 30, 1998 and 1997 (unaudited)               5

           Statements of Cash Flows for the six months ended June 30, 1998 and 1997 (unaudited)                         6

           Notes to Financial Statements (unaudited)                                                                    7

  Item 2.  Management's Discussion and Analysis of Financial Condition and Results of Operations                       10

  Item 3.  Quantitative and Qualitative Disclosures About Market Risk                                                  12


PART II - OTHER INFORMATION

  Item 1.  Legal Proceedings                                                                                           13

  Item 3.  Defaults Upon Senior Securities                                                                             14

  Item 5.  Other Information                                                                                           14

  Item 6.  Exhibits and Reports on Form 8-K                                                                            16
</TABLE>



                                       2

<PAGE>   3

                         PART I - FINANCIAL INFORMATION


  Item 1. Financial Statements

          Presented herein are the Registrant's balance sheets as of June 30,
          1998 and December 31, 1997, statements of operations for the three and
          six months ended June 30, 1998 and 1997, and statements of cash flows
          for the six months ended June 30, 1998 and 1997.





                                       3
<PAGE>   4

                            IEA INCOME FUND XII, L.P.

                                 BALANCE SHEETS

                                   (UNAUDITED)



<TABLE>
<CAPTION>
                                                                                         June 30,        December 31,
                                                                                           1998              1997
                                                                                       ------------      ------------
<S>                                                                                    <C>               <C>         
                                     Assets

Current assets:
    Cash and cash equivalents, includes $2,341,844 at June 30, 1998 and $1,883,189
       at December 31, 1997 in interest-bearing accounts                               $  2,341,944      $  1,883,389
    Net lease receivables due from Leasing Company
       (notes 1 and 2)                                                                      888,697         1,094,453
                                                                                       ------------      ------------

           Total current assets                                                           3,230,641         2,977,842
                                                                                       ------------      ------------

Container rental equipment, at cost                                                      62,929,298        63,162,608
    Less accumulated depreciation                                                        21,283,485        19,524,264
                                                                                       ------------      ------------
       Net container rental equipment                                                    41,645,813        43,638,344
                                                                                       ------------      ------------

                                                                                       $ 44,876,454      $ 46,616,186
                                                                                       ============      ============
                        Liabilities and Partners' Capital

Current liabilities:
    Accrued expenses                                                                   $    462,948      $    462,948
                                                                                       ------------      ------------

           Total current liabilities                                                        462,948           462,948
                                                                                       ------------      ------------

Partners' capital (deficit):
    General partner                                                                         (43,133)          (25,736)
    Limited partners                                                                     44,456,639        46,178,974
                                                                                       ------------      ------------

           Total partners' capital                                                       44,413,506        46,153,238
                                                                                       ------------      ------------

                                                                                       $ 44,876,454      $ 46,616,186
                                                                                       ============      ============
</TABLE>



   The accompanying notes are an integral part of these financial statements.


                                       4


<PAGE>   5

                            IEA INCOME FUND XII, L.P.

                            STATEMENTS OF OPERATIONS

                                   (UNAUDITED)



<TABLE>
<CAPTION>
                                                           Three Months Ended                Six Months Ended
                                                     ----------------------------      ----------------------------
                                                       June 30,          June 30,       June 30,           June 30,
                                                         1998             1997            1998              1997
                                                     -----------      -----------      -----------      -----------
<S>                                                  <C>              <C>              <C>              <C>        
Net lease revenue (notes 1 and 3)                    $ 1,390,908      $ 1,346,583      $ 2,780,862      $ 2,743,047

Other operating expenses:
    Depreciation                                         920,906          972,388        1,842,132        1,958,963
    Other general and administrative expenses             22,960           33,282           51,488           50,541
                                                     -----------      -----------      -----------      -----------
                                                         943,866        1,005,670        1,893,620        2,009,504
                                                     -----------      -----------      -----------      -----------

       Earnings from operations                          447,042          340,913          887,242          733,543

Other income (loss):
    Interest income                                       30,228           21,096           57,694           48,201
    Net gain (loss) on disposal of equipment              (7,738)            (626)          (3,242)           8,702
                                                     -----------      -----------      -----------      -----------
                                                          22,490           20,470           54,452           56,903
                                                     -----------      -----------      -----------      -----------

       Net earnings                                  $   469,532      $   361,383      $   941,694      $   790,446
                                                     ===========      ===========      ===========      ===========

Allocation of net earnings:
    General partner                                  $    53,873      $    62,171      $   116,675      $   139,804
    Limited partners                                     415,659          299,212          825,019          650,642
                                                     -----------      -----------      -----------      -----------
                                                     $   469,532      $   361,383      $   941,694      $   790,446
                                                     ===========      ===========      ===========      ===========

Limited partners' per unit share of net earnings     $      0.11      $      0.09      $      0.23      $      0.19
                                                     ===========      ===========      ===========      ===========
</TABLE>




   The accompanying notes are an integral part of these financial statements.



                                       5
<PAGE>   6

                            IEA INCOME FUND XII, L.P.

                            STATEMENTS OF CASH FLOWS

                                   (UNAUDITED)



<TABLE>
<CAPTION>
                                                                     Six Months Ended
                                                               ----------------------------
                                                                  June 30,         June 30,
                                                                   1998             1997
                                                               -----------      -----------
<S>                                                            <C>              <C>        
Net cash provided by operating activities                      $ 2,811,805      $ 2,931,817

Cash flows provided by (used in) investing activities:
    Proceeds from disposal of equipment                            328,176           83,509
    Purchase of container rental equipment                              --         (374,111)
    Acquisition fees paid to general partner                            --         (168,706)
                                                               -----------      -----------

       Net cash provided by (used in) investing activities         328,176         (459,308)
                                                               -----------      -----------

Cash flows used in financing activities:
    Distribution to partners                                    (2,681,426)      (3,082,099)
                                                               -----------      -----------


Net increase (decrease) in cash and cash equivalents               458,555         (609,590)


Cash and cash equivalents at January 1                           1,883,389        2,262,639
                                                               -----------      -----------


Cash and cash equivalents at June 30                           $ 2,341,944      $ 1,653,049
                                                               ===========      ===========
</TABLE>




   The accompanying notes are an integral part of these financial statements.


                                       6

<PAGE>   7

                            IEA INCOME FUND XII, L.P.

                     NOTES TO UNAUDITED FINANCIAL STATEMENTS


(1)   Summary of Significant Accounting Policies

      (a) Nature of Operations

          IEA Income Fund XII, L.P. (the "Partnership") is a limited partnership
          organized under the laws of the State of California on August 28, 1991
          for the purpose of owning and leasing marine cargo containers. Cronos
          Capital Corp. ("CCC") is the general partner and, with its affiliate
          Cronos Containers Limited (the "Leasing Company"), manages and
          controls the business of the Partnership. The Partnership shall
          continue until December 31, 2011, unless sooner terminated upon the
          occurrence of certain events.

          The Partnership commenced operations on January 31, 1992, when the
          minimum subscription proceeds of $2,000,000 were obtained. As of June
          30, 1998, the Partnership operated 9,275 twenty-foot, 5,263 forty-foot
          and 208 forty-foot high-cube marine dry cargo containers, as well as
          198 twenty-foot and 305 forty-foot marine refrigerated cargo
          containers.

          The Partnership offered 3,750,000 units of limited partnership
          interest at $20 per unit, or $75,000,000. The offering terminated on
          November 30, 1992, at which time 3,513,594 limited partnership units
          had been purchased.

      (b) Leasing Company and Leasing Agent Agreement

          The Partnership has entered into a Leasing Agent Agreement whereby the
          Leasing Company has the responsibility to manage the leasing
          operations of all equipment owned by the Partnership. Pursuant to the
          Agreement, the Leasing Company is responsible for leasing, managing
          and re-leasing the Partnership's containers to ocean carriers and has
          full discretion over which ocean carriers and suppliers of goods and
          services it may deal with. The Leasing Agent Agreement permits the
          Leasing Company to use the containers owned by the Partnership,
          together with other containers owned or managed by the Leasing Company
          and its affiliates, as part of a single fleet operated without regard
          to ownership. Since the Leasing Agent Agreement meets the definition
          of an operating lease in Statement of Financial Accounting Standards
          (SFAS) No. 13, it is accounted for as a lease under which the
          Partnership is lessor and the Leasing Company is lessee.

          The Leasing Agent Agreement generally provides that the Leasing
          Company will make payments to the Partnership based upon rentals
          collected from ocean carriers after deducting direct operating
          expenses and management fees to CCC and the Leasing Company. The
          Leasing Company leases containers to ocean carriers, generally under
          operating leases which are either master leases or term leases (mostly
          two to five years). Master leases do not specify the exact number of
          containers to be leased or the term that each container will remain on
          hire but allow the ocean carrier to pick up and drop off containers at
          various locations; rentals are based upon the number of containers
          used and the applicable per-diem rate. Accordingly, rentals under
          master leases are all variable and contingent upon the number of
          containers used. Most containers are leased to ocean carriers under
          master leases; leasing agreements with fixed payment terms are not
          material to the financial statements. Since there are no material
          minimum lease rentals, no disclosure of minimum lease rentals is
          provided in these financial statements.

      (c) Basis of Accounting

          The Partnership utilizes the accrual method of accounting. Net lease
          revenue is recorded by the Partnership in each period based upon its
          leasing agent agreement with the Leasing Company. Net lease revenue is
          generally dependent upon operating lease rentals from operating lease
          agreements between the Leasing Company and its various lessees, less
          direct operating expenses and management fees due in respect of the
          containers specified in each operating lease agreement.



                                                                     (Continued)


                                       7

<PAGE>   8

                            IEA INCOME FUND XII, L.P.

                     NOTES TO UNAUDITED FINANCIAL STATEMENTS


      (d) Financial Statement Presentation

          These financial statements have been prepared without audit. Certain
          information and footnote disclosures normally included in financial
          statements prepared in accordance with generally accepted accounting
          procedures have been omitted. It is suggested that these financial
          statements be read in conjunction with the financial statements and
          accompanying notes in the Partnership's latest annual report on Form
          10-K.

          The preparation of financial statements in conformity with generally
          accepted accounting principles (GAAP) requires the Partnership to make
          estimates and assumptions that affect the reported amounts of assets
          and liabilities and disclosure of contingent assets and liabilities at
          the date of the financial statements and the reported amounts of
          revenues and expenses during the reported period. Actual results could
          differ from those estimates.

          The interim financial statements presented herewith reflect all
          adjustments of a normal recurring nature which are, in the opinion of
          management, necessary to a fair statement of the financial condition
          and results of operations for the interim periods presented.


(2)   Net Lease Receivables Due from Leasing Company

      Net lease receivables due from the Leasing Company are determined by
      deducting direct operating payables and accrued expenses, base management
      fees payable, and reimbursed administrative expenses payable to CCC and
      its affiliates from the rental billings payable by the Leasing Company to
      the Partnership under operating leases to ocean carriers for the
      containers owned by the Partnership. Net lease receivables at June 30,
      1998 and December 31, 1997 were as follows:


<TABLE>
<CAPTION>
                                                                         June 30,    December 31,
                                                                          1998           1997
                                                                       ----------     ----------
<S>                                                                    <C>            <C>       
            Lease receivables, net of doubtful accounts of $66,415
              at June 30, 1998 and $126,327 at December 31, 1997       $1,877,083     $2,117,313
            Less:
            Direct operating payables and accrued expenses                523,424        512,846
            Damage protection reserve                                     138,142        179,744
            Base management fees                                          289,008        289,537
            Reimbursed administrative expenses                             37,812         40,733
                                                                       ----------     ----------

                                                                       $  888,697     $1,094,453
                                                                       ==========     ==========
</TABLE>




                                                                     (Continued)
                                       8
<PAGE>   9

                            IEA INCOME FUND XII, L.P.

                     NOTES TO UNAUDITED FINANCIAL STATEMENTS


(3)   Net Lease Revenue

      Net lease revenue is determined by deducting direct operating expenses,
      base management fees and reimbursed administrative expenses to CCC and its
      affiliates from the rental revenue billed by the Leasing Company under
      operating leases to ocean carriers for the containers owned by the
      Partnership. Net lease revenue for the three and six-month periods ended
      June 30, 1998 and 1997 was as follows:


<TABLE>
<CAPTION>
                                                       Three Months Ended              Six Months Ended
                                                    -------------------------     -------------------------
                                                     June 30,       June 30,       June 30,        June 30,
                                                       1998           1997           1998            1997
                                                    ----------     ----------     ----------     ----------
<S>                                                 <C>            <C>            <C>            <C>       
            Rental revenue                          $2,137,908     $2,276,081     $4,317,266     $4,612,886
            Less:
            Rental equipment operating expenses        489,908        652,195        977,628      1,311,863
            Base management fees                       144,690        156,321        294,592        318,083
            Reimbursed administrative expenses         112,402        120,982        264,184        239,893
                                                    ----------     ----------     ----------     ----------

                                                    $1,390,908     $1,346,583     $2,780,862     $2,743,047
                                                    ==========     ==========     ==========     ==========
</TABLE>




                                       9

<PAGE>   10

Item 2. Management's Discussion and Analysis of Financial Condition and Results
of Operations

It is suggested that the following discussion be read in conjunction with the
Registrant's most recent annual report on Form 10-K.


1)    Material changes in financial condition between June 30, 1998 and December
      31, 1997.

      At June 30, 1998, the Registrant had $2,341,944 in cash and cash
      equivalents, an increase of $458,555 from the December 31, 1997 cash
      balances. At June 30, 1998, the Registrant had approximately $465,000 in
      cash generated from equipment sales reserved as part of its cash balances.
      Throughout the remainder of 1998, the Registrant expects to continue using
      cash generated from equipment sales to purchase and replace containers
      which have been lost or damaged beyond repair.

      The Registrant's operating performance contributed to a 19% decline in net
      lease receivables at June 30, 1998 when compared to December 31, 1997. The
      Registrant's cash distribution from operations for the second quarter of
      1998 was 7.25% (annualized) of the limited partners' original capital
      contributions, unchanged from the first quarter of 1998. These
      distributions are directly related to the Registrant's results from
      operations and may fluctuate accordingly.

      Imbalances and reductions in trade volumes, fueled by the economic crisis
      in Asia, continue to affect the container leasing market and Partnership
      operations. Containerships leaving Asia are operating at full capacity.
      Yet, on the return eastbound trip they are going back to Asia with only a
      fraction of their holds utilized. This results in a shortage of containers
      available for exporting cargo from Asia and a surplus of containers in
      locations of low demand. As a consequence of this imbalance, container
      leasing companies are repositioning empty containers from low-demand
      locations back to Asian ports in order to keep equipment at the source of
      cargo and, at the same time, reduce the effects of additional depot
      charges for idle equipment and lost revenue. While there is a cost
      incurred when repositioning an empty container, revenue is lost while it
      is in transit. In spite of these market pressures, strong trade with other
      parts of the world is compensating for the imbalances with Asia. There is
      renewed demand for leased containers in locations such as Mexico, Canada,
      China, and areas of Europe where trade volumes of containerized goods are
      prospering. In light of the current market conditions, the Registrant's
      focus remains centered on strategic planning in order to reduce equipment
      imbalances and on improving collections to maximize returns.


2)    Material changes in the results of operations between the three and
      six-month periods ended June 30, 1998 and the three and six-month periods
      ended June 30, 1997.

      Net lease revenue for the three and six-month periods ended June 30, 1998
      was $1,390,908 and $2,780,862, respectively, an increase of 3% and 1%,
      respectively, from the same periods in the prior year. Gross rental
      revenue (a component of net lease revenue) for the three and six-month
      periods ended June 30, 1998 was $2,137,908 and $4,317,266, respectively,
      reflecting a decline of 6% from the same respective periods in the prior
      year. Gross lease revenue was primarily impacted by lower per-diem rental
      rates and utilization levels. Average dry cargo container per-diem rental
      rates for the three and six-month periods ended June 30, 1998 declined
      approximately 7% and 9%, respectively, when compared to the same periods
      in the prior year.





                                       10

<PAGE>   11

      The Registrant's average fleet size and utilization rates for the three
      and six-month periods ended June 30, 1998 and 1997 were as follows:


<TABLE>
<CAPTION>
                                                               Three Months Ended           Six Months Ended
                                                              --------------------        --------------------
                                                              June 30,      June 30,      June 30,      June 30,
                                                               1998          1997          1998          1997
                                                              ------        ------        ------        ------
<S>                                                          <C>           <C>           <C>           <C>   
            Average fleet size (measured in twenty-foot
                equivalent units (TEU))
                   Dry cargo containers                       20,230        20,391        20,257        20,331
                   Refrigerated containers                       808           811           809           811
            Average Utilization
                   Dry cargo containers                           78%           78%           78%           77%
                   Refrigerated containers                        84%           83%           85%           84%
</TABLE>


      Rental equipment operating expenses were 23% of the Registrant's gross
      lease revenue during both the three and six-month periods ended June 30,
      1998, as compared to 29% and 28%, respectively, of the Registrant's gross
      lease revenue during the three and six-month periods ended June 30, 1997.
      This decline was largely attributable to a decrease in costs associated
      with slightly higher utilization levels, including handling and storage.

      The Registrant disposed of 18 twenty-foot and nine forty-foot marine dry
      cargo containers during the second quarter of 1998, as compared to 10
      twenty-foot and 12 forty-foot marine dry cargo containers during the same
      period in the prior year. The decision to repair or dispose of a container
      is made when it is returned by a lessee. This decision is influenced by
      various factors including the age, condition, suitability for continued
      leasing, as well as the geographical location of the container when
      disposed. These factors also influence the amount of sales proceeds
      received and the related gain on container disposals.

      Year 2000

      The Registrant relies upon the financial and operational systems provided
      by the Leasing company and its affiliates, as well as the systems provided
      by other independent third parties to service the three primary areas of
      its business: investor processing/maintenance; container leasing/asset
      tracking; and accounting finance. The Registrant has received confirmation
      from its third-party investor processing/maintenance vendor that their
      system is Year 2000 compliant. The Registrant does not expect a material
      increase in its vendor servicing fee to reimburse Year 2000 costs.
      Container leasing/asset tracking and accounting/finance services are
      provided to the Registrant by CCC and its affiliate, Cronos Containers
      Limited (the "Leasing Company"), pursuant to the respective Limited
      Partnership Agreement and Leasing Agent Agreement. CCC and the Leasing
      Company have initiated a program to prepare their systems and applications
      for the Year 2000. Preliminary studies indicate that testing, conversion
      and upgrading of system applications is expected to cost CCC and the
      Leasing Company less than $500,000. Pursuant to the Limited Partnership
      Agreement, CCC or the Leasing Company, may not seek reimbursement of data
      processing costs associated with the Year 2000 program. The financial
      impact of making these required system changes is not expected to be
      material to the Registrant's financial position, results of operations or
      cash flows.




                                       11
<PAGE>   12

      Cautionary Statement

      This Quarterly Report on Form 10-Q contains statements relating to future
      results of the Registrant, including certain projections and business
      trends, that are "forward-looking statements" as defined in the Private
      Securities Litigation Reform Act of 1995. Actual results may differ
      materially from those projected as a result of certain risks and
      uncertainties, including but not limited to changes in: economic
      conditions; trade policies; demand for and market acceptance of leased
      marine cargo containers; competitive utilization and per-diem rental rate
      pressures; as well as other risks and uncertainties, including but not
      limited to those described in the above discussion of the marine container
      leasing business under Item 2., Management's Discussion and Analysis of
      Financial Condition and Results of Operations; and those detailed from
      time to time in the filings of Registrant with the Securities and Exchange
      Commission.


Item 3.  Quantitative and Qualitative Disclosures About Market Risk

Not applicable.




                                       12
<PAGE>   13

                           PART II - OTHER INFORMATION


Item 1.  Legal Proceedings

         As reported in the Registrant's Current Report on Form 8-K and
         Amendment No. 1 to Current Report on Form 8-K, filed with the
         Commission on February 7, 1997 and February 26, 1997, respectively,
         Arthur Andersen, London, England, resigned as auditors of the Cronos
         Group, a Luxembourg corporation headquartered in Orchard Lea, England
         (the "Parent Company"), on February 3, 1997.

         The Registrant retained a new auditor, Moore Stephens, P.C. on April
         10, 1997, as reported in its Current Report on Form 8-K, filed April
         14, 1997.

         In connection with its resignation, Arthur Andersen also prepared a
         report pursuant to Section 10A(b)(2) of the Securities Exchange Act of
         1934 as amended, for filing by the Parent Company with the Securities
         and Exchange Commission ("SEC") citing its inability to obtain what it
         considered to be adequate responses to its inquiries primarily
         regarding the payment of $1.5 million purportedly in respect of
         professional fees relating to a proposed strategic alliance. This sum
         was returned to the Parent Company in January 1997.

         Following the report of Arthur Andersen, the SEC, on February 10, 1997,
         commenced a private investigation of the Parent Company for the purpose
         of investigating the matters discussed in such report and related
         matters. The SEC's investigation can result in several types of civil
         or administrative sanctions against the Parent Company and individuals
         associated with the Parent Company, including the assessment of
         monetary penalties. Actions taken by the SEC do not preclude additional
         actions by any other federal, civil or criminal authorities or by other
         regulatory organizations or by third parties.

         The SEC's investigation is continuing, and some of the Parent Company's
         present and former officers and directors and others associated with
         the Parent Company have given testimony. However, no conclusion of any
         alleged wrongdoing by the Parent Company or any individual has been
         communicated to the Parent Company by the SEC.

         The Registrant does not believe that the focus of the SEC's
         investigation is upon the Registrant or CCC. CCC is unable to predict
         the outcome of the SEC's ongoing private investigation of the Parent
         Company.

         As reported in the Registrant's Current Report on Form 8-K, filed with
         the SEC on May 21, 1998, the Parent Company reported that its Chairman
         and CEO, Stefan M. Palatin, was suspended from his duties pending the
         investigation of fraud charges against him by Austrian government
         authorities. On June 8, 1998, the Parent Company's Board of Directors
         removed Mr. Palatin as Managing Director and Chief Executive Officer.
         Mr. Palatin resigned from the Board of Directors of the Parent Company
         on July 6, 1998. Mr. Rudolf J. Weissenberger has been appointed to
         replace Mr. Palatin as an executive director and Chief Executive
         Officer. Also, on June 8, 1998, the Board approved a proposal to add
         two independent directors to the Board. The Board engaged legal counsel
         to provide legal advice and commence legal action, if appropriate,
         against former officers or directors of the Parent Company (including
         Mr. Palatin) if it is determined that they engaged in any misfeasance
         or improper self-dealing.

         Mr. Palatin had been a director of CCC; he resigned from his position
         as director on April 23, 1998.

         CCC further understands that Austrian authorities have initiated
         investigations of persons in addition to Mr. Palatin, including Mr.
         Weissenberger and Dr. Axel Friedberg. Dr. Friedberg has been a
         non-executive director of the Parent Company since 1997. Such
         investigations, which are still pending, have not resulted in any
         action being taken against Messrs. Weissenberger or Friedberg, and each
         has informed the Parent Company that they do not believe that there is
         any basis for any action to be taken against them.




                                       13
<PAGE>   14

Item 3.  Defaults Upon Senior Securities

         See Item 5. Other Information.

Item 5.  Other Information

         In 1993, the Parent Company negotiated a credit facility (hereinafter,
         the "Credit Facility") with several banks for the use of the Parent
         Company and its affiliates, including CCC. At December 31, 1996,
         approximately $73,500,000 in principal indebtedness was outstanding
         under the Credit Facility. As a party to the Credit Facility, CCC is
         jointly and severally liable for the repayment of all principal and
         interest owed under the Credit Facility. The obligations of CCC, and
         the five other subsidiaries of the Parent Company that are borrowers
         under the Credit Facility, are guaranteed by the Parent Company.

         Following negotiations in 1997 with the banks providing the Credit
         Facility, an Amended and Restated Credit Agreement was executed in June
         1997, subject to various actions being taken by the Parent Company and
         its subsidiaries, primarily relating to the provision of additional
         collateral. This Agreement was further amended in July 1997 and the
         provisions of the Agreement and its Amendment converted the facility to
         a term loan, payable in installments, with a final maturity date of May
         31, 1998. The terms of the Agreement and its Amendment also provided
         for additional security over shares in the subsidiary of the Parent
         Company that owns the head office of the Parent Company's container
         leasing operations. They also provided for the loans to the former
         Chairman of $5,900,000 and $3,700,000 to be restructured as obligations
         of the former Chairman to another subsidiary of the Parent Company (not
         CCC), together with the pledge to this subsidiary company of 2,030,303
         Common Shares beneficially owned by him in the Parent Company as
         security for these loans. They further provided for the assignment of
         these loans to the lending banks, together with the pledge of 1,000,000
         shares and the assignment of the rights of the Parent Company in
         respect of the other 1,030,303 shares. Additionally, CCC granted the
         lending banks a security interest in the fees to which it is entitled
         for the services it renders to the container leasing partnerships of
         which it acts as general partner, including its fee income payable by
         the Registrant. The Parent Company did not repay the Credit Facility at
         the amended maturity date of May 31, 1998.

         On June 30, 1998, the Parent Company entered into a third amendment
         (the "Third Amendment") to the Credit Facility. The Third Amendment
         became effective as of that date, subject to the satisfaction
         thereafter of various conditions, including: the Parent Company must
         deliver its audited financial statements for 1997 by a specified date
         and; on or prior to July 30, 1998, the Parent Company must furnish
         proof that any defaults under any other indebtedness have been waived
         and must also furnish various legal opinions, officers' certificates
         and other loan documentation. Under the Third Amendment, the remaining
         principal amount of $36,800,000 will be amortized in varying monthly
         amounts commencing on July 31, 1998 with $26,950,000 due on September
         30 and a final maturity date of January 8, 1999. All of these
         conditions will be fulfilled by August 14, 1998.

         The directors of the Parent Company are pursuing alternative sources of
         financing to meet the amended repayment obligations under the Third
         Amendment. Failure to meet revised lending terms would constitute an
         event of default with the lenders. The declaration of an event of
         default would result in further defaults with other lenders under loan
         agreement cross-default provisions. Should a default of the term loans
         be enforced, the Parent Company and CCC may be unable to continue as
         going concerns.

         CCC is currently in discussions with the management of the Parent
         Company to provide assurance that the management of the container
         leasing partnerships managed by CCC, including the Registrant, is not
         disrupted pending a refinancing or reorganization of the indebtedness
         of the Parent Company and its affiliates.




                                       14
<PAGE>   15


         The Registrant is not a borrower under the Credit Facility, and neither
         the containers nor the other assets of the Registrant have been pledged
         as collateral under the Credit Facility.

         CCC is unable to determine the impact, if any, these concerns may have
         on the future operating results and financial condition of the
         Registrant or CCC and the Leasing Company's ability to manage the
         Registrant's fleet in subsequent periods.





                                       15
<PAGE>   16


Item 6.   Exhibits and Reports on Form 8-K

(a)   Exhibits


<TABLE>
<CAPTION>
         Exhibit
           No.                           Description                                   Method of Filing
         -------     --------------------------------------------------------          ----------------
<S>                 <C>                                                               <C>
          3(a)       Limited Partnership Agreement of the Registrant, amended          *
                     and restated as of December 2, 1991

          3(b)       Certificate of Limited Partnership of the Registrant              **

          10         Form of Leasing Agent Agreement with Cronos Containers            ***
                     Limited

          27         Financial Data Schedule                                           Filed with this document
</TABLE>


(b)   Reports on Form 8-K

      On May 21, 1998, the Registrant filed a Report on Form 8-K reporting
      changes on the board of directors of the Parent Company.








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

*     Incorporated by reference to Exhibit "A" to the Prospectus of the
      Registrant dated December 2, 1991, included as part of Registration
      Statement on Form S-1 (No. 33-42697)

**    Incorporated by reference to Exhibit 3.2 to the Registration Statement on
      Form S-1 (No. 33-42697)

***   Incorporated by reference to Exhibit 10.2 to the Registration Statement on
      Form S-1 (No. 33-42697)






                                       16
<PAGE>   17

                                   SIGNATURES


         Pursuant to the requirements of the Securities Exchange Act of 1934,
the Registrant has duly caused this Report to be signed on its behalf by the
undersigned thereunto duly authorized.




                                         IEA INCOME FUND XII, L.P.


                                         By Cronos Capital Corp.
                                            The General Partner




                                         By /s/ Dennis J. Tietz
                                            ----------------------------------
                                            Dennis J. Tietz
                                            President and Director of Cronos
                                            Capital Corp. ("CCC")
                                            Principal Executive Officer of CCC




Date: August 14, 1998




                                       17

<PAGE>   18


                                  EXHIBIT INDEX


<TABLE>
<CAPTION>
         Exhibit
           No.                           Description                                   Method of Filing
         -------     --------------------------------------------------------          ----------------
<S>                 <C>                                                               <C>
          3(a)       Limited Partnership Agreement of the Registrant, amended          *
                     and restated as of December 2, 1991

          3(b)       Certificate of Limited Partnership of the Registrant              **

          10         Form of Leasing Agent Agreement with Cronos Containers            ***
                     Limited

          27         Financial Data Schedule                                           Filed with this document
</TABLE>







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

*     Incorporated by reference to Exhibit "A" to the Prospectus of the
      Registrant dated December 2, 1991, included as part of Registration
      Statement on Form S-1 (No. 33-42697)

**    Incorporated by reference to Exhibit 3.2 to the Registration Statement on
      Form S-1 (No. 33-42697)

***   Incorporated by reference to Exhibit 10.2 to the Registration Statement on
      Form S-1 (No. 33-42697)