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                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549
 
                            ------------------------
   
                                    FORM 10Q/A
    
/X/ QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE
    ACT OF 1934.
 
For the Quarterly period ended December 31, 1997.
 
                                       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 0-14713
 
                                INTERLEAF, INC.
             (EXACT NAME OF REGISTRANT AS SPECIFIED IN ITS CHARTER)
 
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<S>                                            <C>
                Massachusetts                                   04-2729042
        (State or other jurisdiction              (I.R.S. employer identification number)
      of incorporation or organization)
 
        62 Fourth Avenue, Waltham, MA                              02154
  (Address of principal executive offices)                      (Zip Code)
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                                 (781) 290-0710
                        (Registrant's telephone number,
                              including area code)
 
    Indicate by check /X/ 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 last 90 days    Yes /X/  No / /.
 
                      APPLICABLE ONLY TO CORPORATE ISSUERS
 
    The number of shares outstanding of the issuer's Common Stock, $.01 par
value, as of February 10, 1998 was 18,155,309.
 
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                           PART II--OTHER INFORMATION


ITEM 6. EXHIBITS AND REPORTS ON FORM 8-K
 
    (a) The exhibits listed in the accompanying Exhibit Index are filed as part
        of this Quarterly Report on Form 10-Q.
   
    (b) A report on Form 8-K was filed by the Company on October 9, 1997, as 
        amended by Form 8-K/A filed on October 23, 1997.
    
                                   SIGNATURE
 
    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.
 
    February 19, 1998
 
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<S>                                           <C>
                                              /s/ Robert R. Langer
                                              ------------------------------------
                                              Robert R. Langer,
                                              Vice President of Finance and Administration
                                              and Chief Financial Officer
                                              (Principal Financial and Accounting Officer)
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                                       2

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<CAPTION>
EXHIBIT
NUMBER                                      DESCRIPTION                                            METHOD OF FILING
--------                    ----------------------------------------------                         ----------------
<S>        <C>                                                                                           <C>
3(a)       Restated Articles of Organization of the Company, as amended                                  [xviii]

3(b)       By--Laws of the Company, as amended                                                               [v]

4(a)       Specimen Certificate for Shares of the Company's Common Stock                                   [xiv]

4(b)       Rights Agreement, dated July 15, 1988, between the Company and the First National Bank           [xv]
           of Boston

10(a)      Company's 1983 Stock Option Plan, as amended                                                      [v]

10(a1)     1994 Employee Stock Option Plan, as amended                                                    [xiii]

10(a2)     1993 Incentive Stock Option Plan, as amended                                                  [xviii]

10(b)      Company's 1989 Director Stock Option Plan                                                         [i]

10(b2)     Company's 1987 Employee Stock Purchase Plan, as amended                                        [xiii]

10(c)      Company's 1989 Officer and Employee Severance Benefit Plans                                       [i]

10(cc)     Company's 1993 Director Stock Option Plan                                                         [v]

10(d)      Agreements between PruTech Research and Development Partnership III and the Company,             [ii]
           dated October 21, 1988.

10(e)      Exclusive Marketing and Licensing Agreement, between Interleaf South America, Ltd. and            [i]
           the Company, and related Option Agreement, dated March 31, 1989.

10(f)      Distribution and License Agreement between Interleaf Italia, S.r.l. and the Company,              [i]
           and related Joint Venture Agreement, dated October 31, 1988.

10(g)      Preferred Stock Purchase Agreements, for the issuance of 2,142,857 shares of the                 [ii]
           Company's Senior Series B Convertible Preferred Stock, dated September 29, 1989.

10(h)      Notification to Preferred Shareholder of increase in conversion ratio, dated May 18,            [iii]
           1992.

10(i)      Lease of Prospect Place, Waltham, MA, between Prospect Place Limited Partnership and             [iv]
           Interleaf, Inc., and related Agreements, dated March 30, 1990.

10(j)      Employment and severance agreement between the Company and Edward Koepfler, the                 [vii]
           Company's President, dated October 3, 1994.

10(k)      Loan and Security Agreement between the Company and Foothill Capital Corporation,                [ix]
           dated May 2, 1995.

10(l)      Employment and severance agreement between the Company and G. Gordon M. Large, the               [ix]
           Company's Executive Vice President and Chief Financial Officer, dated June 5, 1995.

10(m)      Net Lease, dated August 14, 1995, between Principal Mutual Insurance Company and the              [x]
           Company.

10(n)      Sublease, dated September 15, 1995, between Parametric Technology Corporation and the             [x]
           Company.

10(o)      Employment and severance agreement between the Company and Mark Cieplik, the Company's           [xi]
           Vice President, Americas, dated March 17, 1995.

10(p)      Agreement between PruTech Research and Development Partnership III and the Company,             [xii]
           dated November 14, 1995.

10(q)      Series C Preferred Stock Agreement between Interleaf, Inc. and Lindner Investments,            [xiii]
           dated October 14, 1996.
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                                       3
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<S>                                           <C>                                             <C>  <C>
10(r)      Letter Agreement between the Company and Robert M. Stoddard, as the Company's then              [xvi]
           Vice President of Finance and Administration, and Chief Financial Officer, dated
           November 11, 1996.

10(s)      Letter Agreement between the Company and Rory J. Cowan, the Company's President and             [xvi]
           Chief Executive Officer, dated November 15, 1996, concerning his employment and
           compensation with the Company.

10(t)      Letter Agreement between the Company and Mark H. Cieplik, the Company's Vice President          [xvi]
           of Sales, dated November 15, 1996, concerning his employment and compensation with the
           Company.

10(u)      Letter Agreement between the Company and Michael L. Shanker, the Company's Vice                 [xvi]
           President of Professional Services, dated November 15, 1996, concerning his employment
           and compensation with the Company.

10(v)      Letter Agreement between the Company and Stephen J. Hill, the Company's Vice President          [xvi]
           of Europe, dated November 15, 1996, concerning his employment and compensation with
           the Company.

10(w)      Resignation Agreement and Release and Employment Agreement between Ed Koepfler, the             [xvi]
           Company's former President and Chief Executive Officer, and the Company, dated
           November 15, 1996, concerning his employment and severance with the Company.

10(w1)     Resignation Agreement and Release and Employment Agreement between G. Gordon M. Large,          [xvi]
           the Company's former Executive Vice President of Finance and Administration and Chief
           Financial Officer, and the Company, dated November 12, 1996, concerning his employment
           and severance with the Company.

10(x)      Resignation Agreement and Release and Employment Agreement between Stan Douglas, the            [xvi]
           Company's former Vice President of Engineering Operations, and the Company, dated
           November 15, 1996, concerning his employment and severance with the Company.

10(y)      Terms of Engagement between the Company and Robert R. Langer, Vice President of                 [xvi]
           Finance and Administration and Chief Financial Officer, dated December 30, 1996,
           concerning his employment with the Company.

10(z)      Offer Letter and Acceptance between Jaime W. Ellertson, the Company's President and             [xvi]
           Chief Executive Officer, and the Company, dated January 9, 1997.

10(z1)     Offer Letter and Acceptance between Michael L. Torto, the Company's Vice President,            [xvii]
           Marketing, and the Company, dated March 28, 1997.

10(z2)     Offer Letter and Acceptance between Robert A. Fisher, the Company's Vice President,            [xvii]
           Customer Support, and the Company, dated April 17, 1997.

10(z3)     Offer Letter and Acceptance between Christopher McKee, the Company's Vice President,           [xvii]
           Europe, Middle East, Africa, and the Company, dated May 13, 1997.

10(z4)     Offer Letter and Acceptance between Gary R. Phillips, the Company's Vice President,            [xvii]
           North American Sales, and the Company, dated May 22, 1997.

10(z5)     Resignation Agreement between Mark H. Cieplik, the Company's former Vice President,            [xvii]
           Americas, and the Company, dated May 29, 1997, concerning his employment and severance
           with the Company.

10(z6)     Resignation Agreement between Stephen J. Hill, the Company's former Vice President,            [xvii]
           Europe, and the Company, dated June 5, 1997, concerning his employment and severance
           with the Company.

10(z7)     Offer Letter and Acceptance between Craig Newfield, the Company's Vice President,             [xviii]
           General Counsel & Clerk, and the Company, dated October 3,
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                                       4
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<S>                                           <C>                                             <C>  <C>
           1997.

10(aa)     Preferred Stock Investment Agreement among the Company and certain investors dated as         [xviii]
           of September 30, 1997, with exhibits.

10(bb)     Stock Purchase Warrant and signature pages between the Company and certain family             [xviii]
           members of the principals of Capello Capital Corp. date as of September 30, 1997.

27         Financial Data Schedule                                                                      Included
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<S>        <C>
[i]        Incorporated herein by reference is the applicable Exhibit to Company's Annual Report
           on Form 10-K for the year ended March 31, 1989, File Number 0-14713.
 
[ii]       Incorporated herein by reference is the applicable Exhibit to Company's Annual Report
           on Form 10-K for the year ended March 31, 1990, File Number 0-14713.
 
[iii]      Incorporated herein by reference is the applicable Exhibit to Company's Annual Report
           on Form 10-K for the year ended March 31, 1992, File Number 0-14713.
 
[iv]       Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 8-K filed April 13, 1990, File Number 0-14713.
 
[v]        Incorporated herein by reference is the applicable Exhibit to Company's Annual Report
           on Form 10-K for the year ended March 31, 1994, File Number 0-14713.
 
[vi]       Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended September 30, 1994, File Number 0-14713.
 
[vii]      Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended December 31, 1994, File Number 0-14713.
 
[viii]     Incorporated herein by reference is the applicable Exhibit to Company's Annual Report
           on Form 10-K for the year ended March 31, 1995, File Number 0-14713.
 
[ix]       Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended June 30, 1995, File Number 0-14713.
 
[x]        Incorporated herein by reference is the applicable Exhibit to Company's Registration
           Statement on Form S-2, File Number 33-63785.
 
[xi]       Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended September 30, 1995, File Number 0-14713.
 
[xii]      Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended December 31, 1995, File Number 0-14713.
 
[xiii]     Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended September 30, 1996, File Number 0-14713.
 
[xiv]      Incorporated herein by reference is the applicable Exhibit to Company's Registration
           Statement on Form S-1, File Number 33-5743.
 
[xv]       Incorporated herein by reference is Exhibit 1 to Company's Registration Statement on
           Form 8-A, filed July 27, 1988.
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                                       5
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<S>        <C>
[xvi]      Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended December 31, 1996, File Number 0-14713.
 
[xvii]     Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended June 30, 1997, File Number 0-14713.
 
[xviii]    Incorporated herein by reference is the applicable Exhibit to Company's Report on
           Form 10-Q for the quarter ended September 30, File Number 0-14713.
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                                       6