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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
 
                                  FORM 10-K/A
                                AMENDMENT NO. 1
(MARK ONE)
[ X ]  ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(D) OF
                 THE SECURITIES EXCHANGE ACT OF 1934
 
                  FOR THE FISCAL YEAR ENDED DECEMBER 31, 1996
 
                                       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: 0-17189
 
                          KOLL REAL ESTATE GROUP, INC.
 
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)
 
                    DELAWARE                                02-0426634
          (STATE OR OTHER JURISDICTION                   (I.R.S. EMPLOYER
       OF INCORPORATION OR ORGANIZATION)               IDENTIFICATION NO.)
             4343 VON KARMAN AVENUE
           NEWPORT BEACH, CALIFORNIA                          92660
    (ADDRESS OF PRINCIPAL EXECUTIVE OFFICES)                (ZIP CODE)
 
       REGISTRANT'S TELEPHONE NUMBER, INCLUDING AREA CODE: (714) 833-3030
 
          SECURITIES REGISTERED PURSUANT TO SECTION 12(B) OF THE ACT:
                                      NONE
 
          SECURITIES REGISTERED PURSUANT TO SECTION 12(G) OF THE ACT:
                 CLASS A COMMON STOCK, PAR VALUE $.05 PER SHARE
                                (TITLE OF CLASS)
 
                SERIES A CONVERTIBLE REDEEMABLE PREFERRED STOCK,
                            PAR VALUE $.01 PER SHARE
                                (TITLE OF CLASS)
 
       12% SENIOR SUBORDINATED PAY-IN-KIND DEBENTURES DUE MARCH 15, 2002
                                (TITLE OF CLASS)
 
           12% SUBORDINATED PAY-IN-KIND DEBENTURES DUE MARCH 15, 2002
                                (TITLE OF CLASS)
 
    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 ___
 
    INDICATE BY CHECK MARK IF DISCLOSURE OF DELINQUENT FILERS PURSUANT TO ITEM
405 OF REGULATION S-K IS NOT CONTAINED HEREIN, AND WILL NOT BE CONTAINED, TO THE
BEST OF REGISTRANT'S KNOWLEDGE, IN DEFINITIVE PROXY OR INFORMATION STATEMENTS
INCORPORATED BY REFERENCE IN PART III OF THIS FORM 10-K OR ANY AMENDMENT TO THIS
FORM 10-K. [   ]
 
    THE AGGREGATE MARKET VALUE OF THE VOTING STOCK HELD BY NON-AFFILIATES OF THE
REGISTRANT AS OF JANUARY 31, 1997 WAS $6,069,279.
 
    THE NUMBER OF SHARES OF CLASS A COMMON STOCK OUTSTANDING AS OF JANUARY 31,
1997 WAS 48,938,543.
 
                      DOCUMENTS INCORPORATED BY REFERENCE
 
                                        NONE
 
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EXPLANATORY NOTE:
---------------------
 
    THE REGISTRANT IS AMENDING "NOTE 2--SIGNIFICANT ACCOUNTING POLICIES--REAL
ESTATE" AND "NOTE 3-- ACQUISITIONS AND DISPOSITIONS" TO THE AUDITED HISTORIC
FINANCIAL STATEMENTS SET FORTH IN ITS ANNUAL REPORT ON FORM 10-K FOR THE YEAR
ENDED DECEMBER 31, 1996, WHICH NOTES, AS AMENDED, CORRESPOND TO THE TEXT OF
NOTES AS SET FORTH IN THE REGISTRANT'S REGISTRATION STATEMENT ON FORM S-4, FILE
NO. 333-22121.
 
--------------------------------------------------------------------------------
 
                                    PART IV
 
ITEM 14.  EXHIBITS, FINANCIAL SCHEDULE, AND REPORTS ON FORM 8-K
 
                          KOLL REAL ESTATE GROUP, INC.
 
                 NOTES TO AUDITED HISTORIC FINANCIAL STATEMENTS
 
NOTE 2--SIGNIFICANT ACCOUNTING POLICIES
 
    REAL ESTATE
 
    Real estate held for development and land held for development (real estate
properties) are carried at cost net of impairment losses based on undiscounted
cash flows. Real estate held for sale is carried at cost, net of impairment
losses and selling costs based on undiscounted cash flows. The estimation
process involved in the determination of fair value is inherently uncertain
since it requires estimates as to future events and market conditions. Such
estimation process assumes the Company's ability to complete development and
dispose of its real estate properties in the ordinary course of business based
on management's present plans and intentions. Economic, market, environmental
and political conditions may affect management's development and marketing
plans. In addition, the implementation of such development and marketing plans
could be affected by the availability of future financing for development and
construction activities. Accordingly, the ultimate fair values of the Company's
real estate properties are dependent upon future economic and market conditions,
the availability of financing, and the resolution of political, environmental
and other related issues.
 
    In March 1995, the Financial Accounting Standards Board issued Statement No.
121 "Accounting for the Impairment of Long-Lived Assets and Long-Lived Assets to
be Disposed of" ("SFAS 121"), which requires an impaired asset (real property or
intangible) to be written down to fair value. If an impairment occurs, the fair
value of an asset for purposes of SFAS 121 is deemed to be the amount a willing
buyer would pay a willing seller for such asset in a current transaction. As
required, the Company adopted SFAS 121 during the quarter ended March 31, 1996
which did not have any effect on its financial statements. The Company is
currently implementing an Exchange Offer to deleverage its capital structure as
discussed in Note 6. Under the Exchange Offer as proposed, no revaluation of
real estate properties would be required based on undiscounted cash flows. If an
alternative recapitalization is implemented by the Company pursuant to Court
confirmation of a Prepackaged Plan of reorganization, the Company would apply
the principles required by the American Institute of Certified Public
Accountant's Statement of Position 90-7, "Financial Reporting by Entities in
Reorganization Under the Bankruptcy Code" ("Fresh Start Accounting") and the
carrying value of real estate properties would be adjusted to fair value.
 
    The cost of sales of multi-unit projects is generally computed using the
relative sales value method, with direct construction costs and property taxes
accumulated by phase, using the specific identification method. Interest cost is
capitalized to real estate projects during their development and construction
period.
<PAGE>
                          KOLL REAL ESTATE GROUP, INC.
 
           NOTES TO AUDITED HISTORIC FINANCIAL STATEMENTS (CONTINUED)
 
NOTE 2--SIGNIFICANT ACCOUNTING POLICIES (CONTINUED)
    Operating properties are generally depreciated utilizing the straight-line
method over estimated lives ranging principally from 5 to 7 years. Accumulated
depreciation amounted to $1.1 million and $1.0 million at December 31, 1995 and
1996, respectively.
 
NOTE 3--ACQUISITIONS AND DISPOSITIONS
 
    In November 1994, the Company acquired the stock of Kathryn G. Thompson
Company ("KGTC") and related assets. The principal activities of the acquired
business are residential real estate development and homebuilding, focusing on
the entry-level and first time move-up market segments. The principal project of
the acquired business is a 49% general partnership interest in a 230-acre
project planned for approximately 1,200 residential units in Aliso Viejo in
southern Orange County ("AV Partnership"). In connection with the acquisition,
the Company paid $1.2 million in cash and a $.5 million note, issued 2 million
shares of Class A Common Stock and warrants to purchase an additional 2 million
shares. The Company guaranteed approximately $4.8 million of capital
contribution notes related to the Aliso Viejo partnership interest, which notes
are primarily payable out of positive net cash flow to be generated by the
partnership interest and are not due until the earlier of the completion of the
project or April 1999. In addition, in November 1994, Ms. Kathryn G. Thompson,
who was appointed as a director of the Company, entered into a covenant not to
compete with the Company with respect to real estate development, subject to
certain limited exceptions. Ms. Thompson resigned as an officer and director of
the Company effective November 1, 1996. In conjunction with her resignation, the
covenant of Ms. Thompson was released.
 
    Summarized financial information of AV Partnership is presented below at
December 31, 1995 and 1996 and for the years then ended (in millions):
 
<TABLE>
<CAPTION>
                                                                           1995         1996
                                                                        -----------  -----------
<S>                                                                     <C>          <C>
Balance Sheet Data:
  Total assets........................................................   $   111.9    $   102.5
  Total project debt and other liabilities............................       107.9        110.5
                                                                        -----------  -----------
  Partners' capital...................................................   $     4.0    $    (8.0)
                                                                        -----------  -----------
                                                                        -----------  -----------
Statement of Operations Data:
  Revenues............................................................   $  --        $    44.3
  Expenses............................................................        (4.1)       (55.3)
                                                                        -----------  -----------
  Net loss............................................................   $    (4.1)   $   (11.0)
                                                                        -----------  -----------
                                                                        -----------  -----------
</TABLE>
 
    The Company uses the equity method to account for its investment in AV
Partnership and accordingly, the statement of operations includes a $.1 million
loss for the period from the acquisition date through December 31, 1994, and
losses of $2.0 million and $1.2 million, respectively, for the years ended
December 31, 1995 and 1996. The loss recorded in 1996 reflects accrued interest
on guaranteed capital contribution notes only, as the Company's net investment
is $0 and the recorded liability reflects the Company's guaranty of capital
contribution notes due to the partnership discussed below. Due to a significant
shortfall in sales during 1995 versus forecast, the financial structure of the
partnership and the significant amount of participating mortgages with
preference to the Company's equity interest, the Company does not expect to
receive a financial return from this partnership and in 1995 reserved for its
guaranty of $4.8 million of capital contribution notes. In 1996, certain
information came to the Company's attention concerning the enforceability of the
Company's guarantee of $4.8 million of capital contribution notes. While the
Company has reserved for this guarantee, the Company intends to dispute the
enforceability of the guarantee. The reserve relating to the guaranteed capital
contribution notes, including
<PAGE>
                          KOLL REAL ESTATE GROUP, INC.
 
           NOTES TO AUDITED HISTORIC FINANCIAL STATEMENTS (CONTINUED)
 
NOTE 3--ACQUISITIONS AND DISPOSITIONS (CONTINUED)
accrued interest, for this partnership of $4.8 million and $6.0 million at
December 31, 1995 and 1996, respectively, is included in other liabilities.
 
    In December 1993, the Company completed a transaction with Libra whereby it
exchanged the Company's Lake Superior Land Company subsidiary for approximately
$42.4 million in aggregate face amount of Senior Subordinated Debentures held by
Libra, and net cash proceeds to be generated by Libra's periodic sale of up to
approximately 3.4 million shares of the Company's Class A Common Stock held by
Libra through a series of transactions to be effected in an orderly manner. The
Company also completed a separate transaction with Libra in December 1993,
whereby the Company exchanged approximately 3.4 million newly issued shares of
its Class A Common Stock for approximately $10.6 million in aggregate face
amount of Subordinated Debentures held by Libra. The shares issued to Libra were
deposited in a custodial account for periodic sale in accordance with
instructions from the Company. In February 1994, the Company received $1 million
in cash from Libra in exchange for the immediate termination of a contingent
payment provision of the December 1993 transaction with Libra.
<PAGE>
                                   SIGNATURES
 
    Pursuant to the requirements of Section 13 or 15(d) of the Securities Act of
1934, the Registrant has caused this report to be signed on its behalf by the
undersigned, thereunto duly authorized.
 
Date: April 29, 1997                    KOLL REAL ESTATE GROUP, INC.
 
                                          By: /s/ Raymond J. Pacini
                                             -----------------------------------
                                             Raymond J. Pacini
                                             EXECUTIVE VICE PRESIDENT AND
                                             CHIEF FINANCIAL OFFICER
 
    Pursuant to the requirements of the Securities Act of 1934, this report has
been signed below by the following persons on behalf of the registrant and in
the capacities and on the date indicated.
 
<TABLE>
<CAPTION>
                          SIGNATURE                                         TITLE                    DATE
--------------------------------------------------------------  ------------------------------  --------------
<C>                                                             <S>                             <C>
                           /s/ Donald M. Koll                   Chairman of the Board and
            -------------------------------------                Chief Executive Officer        April 29, 1997
                       (Donald M. Koll)                          (Principal Executive Officer)
 
                                                                Executive Vice President and
                         /s/ Raymond J. Pacini                   Chief Financial Officer
            -------------------------------------                (Principal Financial           April 29, 1997
                     (Raymond J. Pacini)                         and Accounting Officer)
 
                              /s/ Ray Wirta
            -------------------------------------               Director                        April 29, 1997
                         (Ray Wirta)
 
                       /s/ Harold A. Ellis, Jr.
            -------------------------------------               Director                        April 29, 1997
                    (Harold A. Ellis, Jr.)
 
                          /s/ Paul C. Hegness
            -------------------------------------               Director                        April 29, 1997
                      (Paul C. Hegness)
 
                         /s/ J. Thomas Talbot
            -------------------------------------               Director                        April 29, 1997
                      (J. Thomas Talbot)
 
                          /s/ Marco F. Vitulli
            -------------------------------------               Director                        April 29, 1997
                      (Marco F. Vitulli)
</TABLE>