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                                                                    Exhibit 10.1

                      BOSTON PROPERTIES LIMITED PARTNERSHIP

                           Forty-Seventh Amendment to
                        Agreement of Limited Partnership

     This Amendment is made as of April 11, 2003, by BOSTON PROPERTIES, INC., a
Delaware corporation, as general partner (the "GENERAL PARTNER" or the
"COMPANY"), of BOSTON PROPERTIES LIMITED PARTNERSHIP, a Delaware limited
partnership (the "PARTNERSHIP"), for the purpose of amending the Second Amended
and Restated Agreement of Limited Partnership of the Partnership dated June 29,
1998, as amended (the "PARTNERSHIP AGREEMENT"). All capitalized terms used
herein and not defined shall have the respective meanings ascribed to them in
the Partnership Agreement.

     WHEREAS, Section 14.1.B(3) of the Partnership Agreement permits the General
Partner, without the consent of the Limited Partners, to amend the Partnership
Agreement for the purpose of setting forth and reflecting in the Partnership
Agreement the designations, rights, powers, duties, and preferences of holders
of any additional Partnership Interests issued pursuant to Section 4.2.A of the
Partnership Agreement; and

     WHEREAS, the General Partner desires by this Certificate to so amend the
Partnership Agreement as of this 11th day of April, 2003.

     WHEREAS, Pursuant to the Boston Properties, Inc. 1997 Stock Option and
Incentive Plan, as amended and/or one or more successor or additional equity
incentive plans or programs that the Company or the Partnership may adopt after
the date hereof, as amended (each individually and all of them collectively, as
the context requires, the "Plan"), the General Partner resolved to grant to
executives of the Company and its subsidiaries, including the Partnership, Other
Stock-Based Awards (as defined in the Plan) which include the issuance to such
executives of a Partnership Interest having the rights, voting powers,
restrictions, limitations as to distributions, qualifications and terms and
conditions of redemption and conversion set forth herein, such Partnership
Interest to be expressed as a number of Partnership Units to be referred to as
Long Term Incentive Units ("LTIP UNITS").

     WHEREAS, the issuance of LTIP Units is permitted by Section 4.2.A of the
Partnership Agreement.

     NOW, THEREFORE, the General Partner has set forth in this Amendment
pursuant to its authority under Sections 4.2A and 5.4 of the Partnership
Agreement the following description of the rights, voting powers, restrictions,
limitations as to distributions, qualifications and terms and conditions of
redemption and conversion of a class and series of Partnership Interest which
shall be referred to as "LTIP UNITS":

1.   ADDITIONAL DEFINED TERMS. The following additional defined terms shall be
     inserted in Article 1 of the Partnership Agreement, in alphabetical order:

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               "ADJUSTMENT EVENT" shall have the meaning set forth in Section
          4.2.C hereof.

               "COMMON UNIT DISTRIBUTION" shall have the meaning set forth in
          Section 4.2.C hereof.

               "COMMON UNIT ECONOMIC BALANCE" has the meaning set forth in
          Section 6.1.B(iii).

               "CONSTITUENT PERSON" shall have the meaning set forth in Section
          8.8.F.

               "CONVERSION DATE" shall have the meaning set forth in Section
          8.8.B.

               "CONVERSION NOTICE" shall have the meaning set forth in Section
          8.8.B.

               "CONVERSION RIGHT" shall have the meaning set forth in Section
          8.8.A.

               "DISTRIBUTION PAYMENT DATE" shall mean the dates upon which the
          General Partner makes distributions in accordance with Section 5.1 of
          the Partnership Agreement.

               "ECONOMIC CAPITAL ACCOUNT BALANCE" has the meaning set forth in
          Section 6.1.B(iii).

               "FORCED CONVERSION" shall have the meaning set forth in Section
          8.8.C.

               "FORCED CONVERSION NOTICE" shall have the meaning set forth in
          Section 8.8.C.

               "LTIP UNIT" means a Partnership Unit which is designated as an
          LTIP Unit and which has the rights, preferences and other privileges
          designated in Section 4.2.C hereof and elsewhere in the Partnership in
          respect of LTIP Unitholders. The allocation of LTIP Units among the
          Partners shall be set forth on EXHIBIT A, as may be amended from time
          to time.

               "LTIP UNITHOLDER" means a Partner that holds LTIP Units.

               "TRANSACTION" shall have the meaning set forth in Section 8.8.F.

               "VESTING AGREEMENT" means each or any, as the context implies,
          Long Term Incentive Plan (LTIP) Vesting Agreement entered into by a
          LTIP Unitholder upon acceptance of an award of LTIP Units under the
          Plan (as such agreement may be amended, modified or supplemented from
          time to time).

2.   ISSUANCE OF LTIP UNITS. The following subsection C shall be appended to
     Section 4.2 of the Partnership Agreement:

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               C.   The General Partner may from time to time issue LTIP Units
          to Persons who provide services to the Partnership, for such
          consideration as the General Partner may determine to be appropriate,
          and admit such Persons as Limited Partners. Subject to the following
          provisions of this Section 4.2.C and the special provisions of
          Sections 6.1.B(iii), 8.8 and 8.9, LTIP Units shall be treated as
          Common Units, with all of the rights, privileges and obligations
          attendant thereto. For purposes of computing the Partners' Percentage
          Interests, holders of LTIP Units shall be treated as Common
          Unitholders and LTIP Units shall be treated as Common Units. In
          particular, the Partnership shall maintain at all times a one-to-one
          correspondence between LTIP Units and Common Units for conversion,
          distribution and other purposes, including without limitation
          complying with the following procedures:

                    (i)    If an Adjustment Event (as defined below) occurs,
               then the General Partner shall make a corresponding adjustment to
               the LTIP Units to maintain a one-for-one conversion and economic
               equivalence ratio between Common Units and LTIP Units. The
               following shall be "ADJUSTMENT EVENTS": (A) the Partnership makes
               a distribution on all outstanding Common Units in Partnership
               Units, (B) the Partnership subdivides the outstanding Common
               Units into a greater number of units or combines the outstanding
               Common Units into a smaller number of units, or (C) the
               Partnership issues any Partnership Units in exchange for its
               outstanding Common Units by way of a reclassification or
               recapitalization of its Common Units. If more than one Adjustment
               Event occurs, the adjustment to the LTIP Units need be made only
               once using a single formula that takes into account each and
               every Adjustment Event as if all Adjustment Events occurred
               simultaneously. For the avoidance of doubt, the following shall
               not be Adjustment Events: (x) the issuance of Partnership Units
               in a financing, reorganization, acquisition or other similar
               business transaction, (y) the issuance of Partnership Units
               pursuant to any employee benefit or compensation plan or
               distribution reinvestment plan, or (z) the issuance of any
               Partnership Units to the Company in respect of a capital
               contribution to the Partnership of proceeds from the sale of
               securities by the Company. If the Partnership takes an action
               affecting the Common Units other than actions specifically
               described above as "Adjustment Events" and in the opinion of the
               General Partner such action would require an adjustment to the
               LTIP Units to maintain the one-to-one correspondence described
               above, the General Partner shall have the right to make such
               adjustment to the LTIP Units, to the extent permitted by law and
               by the Plan, in such manner and at such time as the General
               Partner, in its sole discretion, may determine to be appropriate
               under the circumstances. If an adjustment is made to the LTIP
               Units as herein provided the Partnership shall promptly file in
               the books and records of the Partnership an officer's certificate
               setting forth such adjustment and a brief statement of the facts
               requiring such adjustment, which certificate shall be conclusive
               evidence of the correctness of such adjustment absent manifest
               error. Promptly after filing of such certificate,

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               the Partnership shall mail a notice to each LTIP Unitholder
               setting forth the adjustment to his or her LTIP Units and the
               effective date of such adjustment; and

                    (ii)   The LTIP Unitholders shall, in respect of each
               Distribution Payment Date, when, as and if authorized and
               declared by the General Partner out of assets legally available
               for that purpose, be entitled to receive distributions in an
               amount per LTIP Unit equal to the distributions per Common Unit
               (the "COMMON UNIT DISTRIBUTION"), paid to holders of record on
               the same record date established by the General Partner with
               respect to such Distribution Payment Date. The term "NEWLY ISSUED
               UNIT" as defined in Section 5.1.B shall be deemed to include LTIP
               Units issued during a Distribution Period and such Section 5.1.B.
               shall apply in full to LTIP Units. During any Distribution
               Period, so long as any LTIP Units are outstanding, no
               distributions (whether in cash or in kind) shall be authorized,
               declared or paid on Common Units, unless equal distributions have
               been or contemporaneously are authorized, declared and paid on
               the LTIP Units for such Distribution Period.

               The LTIP Units shall rank PARI PASSU with the Common Units as to
          the payment of regular and special periodic or other distributions and
          distribution of assets upon liquidation, dissolution or winding up. As
          to the payment of distributions and as to distribution of assets upon
          liquidation, dissolution or winding up, any class or series of
          Partnership Units or Partnership Interests which by its terms
          specifies that it shall rank junior to, on a parity with, or senior to
          the Common Units shall also rank junior to, or PARI PASSU with, or
          senior to, as the case may be, the LTIP Units. Subject to the terms of
          any Vesting Agreement, a LTIP Unitholder shall be entitled to transfer
          his or her LTIP Units to the same extent, and subject to the same
          restrictions as holders of Common Units are entitled to transfer their
          Common Units pursuant to Article 11.

               LTIP Units shall be subject to the following special provisions:

                    (i)    VESTING AGREEMENTS. LTIP Units may, in the sole
               discretion of the General Partner, be issued subject to vesting,
               forfeiture and additional restrictions on transfer pursuant to
               the terms of a Vesting Agreement. The terms of any Vesting
               Agreement may be modified by the General Partner from time to
               time in its sole discretion, subject to any restrictions on
               amendment imposed by the relevant Vesting Agreement or by the
               Plan, if applicable. LTIP Units that have vested under the terms
               of a Vesting Agreement are referred to as "VESTED LTIP UNITS";
               all other LTIP Units shall be treated as "UNVESTED INCENTIVE
               UNITS."

                    (ii)   FORFEITURE. Unless otherwise specified in the Vesting
               Agreement, upon the occurrence of any event specified in a
               Vesting Agreement as resulting in either the right of the
               Partnership or the General Partner to repurchase LTIP Units at a
               specified purchase price or some

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               other forfeiture of any LTIP Units, then if the Partnership or
               the General Partner exercises such right to repurchase or
               forfeiture in accordance with the applicable Vesting Agreement,
               then the relevant LTIP Units shall immediately, and without any
               further action, be treated as cancelled and no longer outstanding
               for any purpose. Unless otherwise specified in the Vesting
               Agreement, no consideration or other payment shall be due with
               respect to any LTIP Units that have been forfeited, other than
               any distributions declared with respect to a Partnership Record
               Date prior to the effective date of the forfeiture. In connection
               with any repurchase or forfeiture of LTIP Units, the balance of
               the portion of the Capital Account of the LTIP Unitholder that is
               attributable to all of his or her LTIP Units shall be reduced by
               the amount, if any, by which it exceeds the target balance
               contemplated by Section 6.1.B(iii), calculated with respect to
               the LTIP Unitholder's remaining LTIP Units, if any.

                    (iii)  ALLOCATIONS. LTIP Unitholders shall be entitled to
               certain special allocations of gain under Section 6.1.B(iii).

                    (iv)   REDEMPTION. The Redemption Right provided to Limited
               Partners under Section 8.6 shall not apply with respect to LTIP
               Units unless and until they are converted to Common Units as
               provided in clause (vi) below and Section 8.8.

                    (v)    LEGEND. Any certificate evidencing an LTIP Unit shall
               bear an appropriate legend indicating that additional terms,
               conditions and restrictions on transfer, including without
               limitation any Vesting Agreement, apply to the LTIP Unit.

                    (vi)   CONVERSION TO COMMON UNITS. Vested LTIP Units are
               eligible to be converted into Common Units under Section 8.8.

                    (vii)  VOTING. LTIP Units shall have the voting rights
               provided in Section 8.9.

3.   SPECIAL ALLOCATION OF GAIN TO LTIP UNITHOLDERS.  The following clause (iii)
     shall be appended to Section 6.1.B of the Partnership Agreement:

               (iii) Notwithstanding the provisions of Section 6.1.A above, but
          subject to the prior allocation of Net Income and gross items of
          income under clauses (i) and (ii) above, any net capital gains
          realized in connection with the actual or hypothetical sale of all or
          substantially all of the assets of the Partnership, including but not
          limited to net capital gain realized in connection with an adjustment
          to the Carrying Value of Partnership assets under Section 704(b) of
          the Code, shall first be allocated to the LTIP Unitholders until the
          Economic Capital Account Balances of such Limited Partners, to the
          extent attributable to their ownership of LTIP Units, are equal to (i)
          the Common Unit Economic Balance, multiplied by (ii) the number of
          their LTIP Units. For this purpose, the

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          "ECONOMIC CAPITAL ACCOUNT BALANCES" of the LTIP Unitholders will be
          equal to their Capital Account balances, plus the amount of their
          shares of any Partner Minimum Gain or Partnership Minimum Gain, in
          either case to the extent attributable to their ownership of LTIP
          Units. Similarly, the "COMMON UNIT ECONOMIC BALANCE" shall mean (i)
          the Capital Account Balance of the Company, plus the amount of the
          Company's share of any Partner Minimum Gain or Partnership Minimum
          Gain, in either case to the extent attributable to the Company's
          ownership of Common Units and computed on a hypothetical basis after
          taking into account all allocations through the date on which any
          allocation is made under this clause 6.1.B(iii), divided by (ii) the
          number of the Company's Common Units. Any such allocations shall be
          made among the LTIP Unitholders in proportion to the amounts required
          to be allocated to each under this clause 6.1.B(iii). The parties
          agree that the intent of this clause 6.1.B(iii) is to make the Capital
          Account balances of the LTIP Unitholders with respect to their LTIP
          Units economically equivalent to the Capital Account balance of the
          Company with respect to its Common Units.

4.   CONVERSION OF LTIP UNITS.  The following Section 8.8 shall be appended to
     Article 8 of the Partnership Agreement.

               Section 8.8 CONVERSION OF LTIP UNITS.

               A.   A LTIP Unitholder shall have the right (the "CONVERSION
          RIGHT"), at his or her option, at any time to convert all or a portion
          of his or her Vested LTIP Units into Common Units; PROVIDED, HOWEVER,
          that a holder may not exercise the Conversion Right for less than
          three hundred (300) Vested LTIP Units or, if such holder holds less
          than one thousand Vested LTIP Units, all of the Vested LTIP Units held
          by such holder. LTIP Unitholders shall not have the right to convert
          Unvested Incentive Units into Common Units until they become Vested
          LTIP Units; PROVIDED, HOWEVER, that when a LTIP Unitholder is notified
          of the expected occurrence of an event that will cause his or her
          Unvested Incentive Units to become Vested LTIP Units, such LTIP
          Unitholder may give the Partnership a Conversion Notice conditioned
          upon and effective as of the time of vesting and such Conversion
          Notice, unless subsequently revoked by the LTIP Unitholder, shall be
          accepted by the Partnership subject to such condition. The General
          Partner shall have the right at any time to cause a conversion of
          Vested LTIP Units into Common Units. In all cases, the conversion of
          any LTIP Units into Common Units shall be subject to the conditions
          and procedures set forth in this Section 8.8.

               B.   A holder of Vested LTIP Units may convert such Units into an
          equal number of fully paid and non-assessable Common Units, giving
          effect to all adjustments (if any) made pursuant to Section 4.2.C.
          Notwithstanding the foregoing, in no event may a holder of Vested LTIP
          Units convert a number of Vested LTIP Units that exceeds (x) the
          Economic Capital Account Balance of such Limited Partner, to the
          extent attributable to its ownership of LTIP Units,

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          divided by (y) the Common Unit Economic Balance, in each case as
          determined as of the effective date of conversion (the "CAPITAL
          ACCOUNT LIMITATION").

               In order to exercise his or her Conversion Right, a LTIP
          Unitholder shall deliver a notice (a "CONVERSION NOTICE") in the form
          attached as EXHIBIT A to the Partnership (with a copy to the General
          Partner) not less than 10 nor more than 60 days prior to a date (the
          "CONVERSION DATE") specified in such Conversion Notice; PROVIDED,
          HOWEVER, that if the General Partner has not given to the LTIP
          Unitholders notice of a proposed or upcoming Transaction (as defined
          below) at least thirty (30) days prior to the effective date of such
          Transaction, then LTIP Unitholders shall have the right to deliver a
          Conversion Notice until the earlier of (x) the tenth (10th) day after
          such notice from the General Partner of a Transaction or (y) the third
          business day immediately preceding the effective date of such
          Transaction. A Conversion Notice shall be provided in the manner
          provided in Section 15.1. Each LTIP Unitholder covenants and agrees
          with the Partnership that all Vested LTIP Units to be converted
          pursuant to this Section 8.8A shall be free and clear of all liens.
          Notwithstanding anything herein to the contrary, a holder of LTIP
          Units may deliver a Redemption Notice pursuant to Section 8.6A of the
          Partnership Agreement relating to those Common Units that will be
          issued to such holder upon conversion of such LTIP Units into Common
          Units in advance of the Conversion Date; PROVIDED, HOWEVER, that the
          redemption of such Common Units by the Partnership shall in no event
          take place until after the Conversion Date. For clarity, it is noted
          that the objective of this paragraph is to put a LTIP Unitholder in a
          position where, if he or she so wishes, the Common Units into which
          his or her Vested LTIP Units will be converted can be redeemed by the
          Partnership simultaneously with such conversion, with the further
          consequence that, if the Company elects to assume the Partnership's
          redemption obligation with respect to such Common Units under Section
          8.6B of the Partnership Agreement by delivering to such holder REIT
          Shares rather than cash, then such holder can have such REIT Shares
          issued to him or her simultaneously with the conversion of his or her
          Vested LTIP Units into Common Units. The General Partner shall
          cooperate with a LTIP Unitholder to coordinate the timing of the
          different events described in the foregoing sentence.

               C.   The Partnership, at any time at the election of the General
          Partner, may cause any number of Vested LTIP Units held by a LTIP
          Unitholder to be converted (a "FORCED CONVERSION") into an equal
          number of Common Units, giving effect to all adjustments (if any) made
          pursuant to Section 4.2.C; provided, however, that the Partnership may
          not cause Forced Conversion of any LTIP Units that would not at the
          time be eligible for conversion at the option of such LTIP Unitholder
          pursuant to Section 8.8.B. In order to exercise its right of Forced
          Conversion, the Partnership shall deliver a notice (a "FORCED
          CONVERSION NOTICE") in the form attached as EXHIBIT B to the
          applicable LTIP Unitholder not less than 10 nor more than 60 days
          prior to the Conversion Date specified in such Forced Conversion
          Notice. A Forced Conversion Notice shall be provided in the manner
          provided in Section 15.1.

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               D.   A conversion of Vested LTIP Units for which the holder
          thereof has given a Conversion Notice or the Partnership has given a
          Forced Conversion Notice shall occur automatically after the close of
          business on the applicable Conversion Date without any action on the
          part of such LTIP Unitholder, as of which time such LTIP Unitholder
          shall be credited on the books and records of the Partnership with the
          issuance as of the opening of business on the next day of the number
          of Common Units issuable upon such conversion. After the conversion of
          LTIP Units as aforesaid, the Partnership shall deliver to such LTIP
          Unitholder, upon his or her written request, a certificate of the
          General Partner certifying the number of Common Units and remaining
          LTIP Units, if any, held by such person immediately after such
          conversion. The Assignee of any Limited Partner pursuant to Section 11
          hereof may exercise the rights of such Limited Partner pursuant to
          this Section 8.8 and such Limited Partner shall be bound by the
          exercise of such rights by the Assignee.

               E.   For purposes of making future allocations under Section
          6.1.B(iii) and applying the Capital Account Limitation, the portion of
          the Economic Capital Account balance of the applicable LTIP Unitholder
          that is treated as attributable to his or her LTIP Units shall be
          reduced, as of the date of conversion, by the product of the number of
          LTIP Units converted and the Common Unit Economic Balance.

               F.   If the Partnership or the General Partner shall be a party
          to any transaction (including without limitation a merger,
          consolidation, unit exchange, self tender offer for all or
          substantially all Common Units or other business combination or
          reorganization, or sale of all or substantially all of the
          Partnership's assets, but excluding any transaction which constitutes
          an Adjustment Event) in each case as a result of which Common Units
          shall be exchanged for or converted into the right, or the holders of
          such Units shall otherwise be entitled, to receive cash, securities or
          other property or any combination thereof (each of the foregoing being
          referred to herein as a "Transaction"), then the General Partner
          shall, immediately prior to the Transaction, exercise its right to
          cause a Forced Conversion with respect to the maximum number of LTIP
          Units then eligible for conversion, taking into account any
          allocations that occur in connection with the Transaction or that
          would occur in connection with the Transaction if the assets of the
          Partnership were sold at the Transaction price or, if applicable, at a
          value determined by the General Partner in good faith using the value
          attributed to the Partnership Units in the context of the Transaction
          (in which case the Conversion Date shall be the effective date of the
          Transaction).

               In anticipation of such Forced Conversion and the consummation of
          the Transaction, the Partnership shall use commercially reasonable
          efforts to cause each LTIP Unitholder to be afforded the right to
          receive in connection with such Transaction in consideration for the
          Common Units into which his or her LTIP Units will be converted the
          same kind and amount of cash, securities and other property (or any
          combination thereof) receivable upon the consummation of such

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          Transaction by a holder of the same number of Common Units, assuming
          such holder of Common Units is not a Person with which the Partnership
          consolidated or into which the Partnership merged or which merged into
          the Partnership or to which such sale or transfer was made, as the
          case may be (a "CONSTITUENT PERSON"), or an affiliate of a Constituent
          Person. In the event that holders of Common Units have the opportunity
          to elect the form or type of consideration to be received upon
          consummation of the Transaction, prior to such Transaction the General
          Partner shall give prompt written notice to each LTIP Unitholder of
          such election, and shall use commercially reasonable efforts to afford
          the LTIP Unitholders the right to elect, by written notice to the
          General Partner, the form or type of consideration to be received upon
          conversion of each LTIP Unit held by such holder into Common Units in
          connection with such Transaction. If a LTIP Unitholder fails to make
          such an election, such holder (and any of its transferees) shall
          receive upon conversion of each LTIP Unit held him or her (or by any
          of his or her transferees) the same kind and amount of consideration
          that a holder of a Common Unit would receive if such Common Unit
          holder failed to make such an election.

               Subject to the rights of the Partnership and the Company under
          any Vesting Agreement and the Plan (including without limitation
          pursuant to Section 3 of the Plan with respect to recapitalizations,
          mergers and substitute awards), the Partnership shall use commercially
          reasonable effort to cause the terms of any Transaction to be
          consistent with the provisions of this Section 8.8.F and to enter into
          an agreement with the successor or purchasing entity, as the case may
          be, for the benefit of any LTIP Unitholders whose LTIP Units will not
          be converted into Common Units in connection with the Transaction that
          will (i) contain provisions enabling the holders of LTIP Units that
          remain outstanding after such Transaction to convert their LTIP Units
          into securities as comparable as reasonably possible under the
          circumstances to the Common Units and (ii) preserve as far as
          reasonably possible under the circumstances the distribution, special
          allocation, conversion, and other rights set forth in the Partnership
          Agreement for the benefit of the LTIP Unitholders.

5.   VOTING RIGHTS OF LTIP UNITS.  The following Section 8.9 shall be appended
     to Article 8 of the Partnership Agreement:

               Section 8.9 VOTING RIGHTS OF LTIP UNITS. LTIP Unitholders shall
          (a) have those voting rights required from time to time by applicable
          law, if any, (b) have the same voting rights as a holder of Common
          Units, with the LTIP Units voting as a single class with the Common
          Units and having one vote per LTIP Unit; and (c) have the additional
          voting rights that are expressly set forth below. So long as any LTIP
          Units remain outstanding, the Partnership shall not, without the
          affirmative vote of the holders of at least a majority of the LTIP
          Units outstanding at the time, given in person or by proxy, either in
          writing or at a meeting (voting separately as a class), amend, alter
          or repeal, whether by merger, consolidation or otherwise, the
          provisions of the Partnership Agreement

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          applicable to LTIP Units so as to materially and adversely affect any
          right, privilege or voting power of the LTIP Units or the LTIP
          Unitholders as such, unless such amendment, alteration, or repeal
          affects equally, ratably and proportionately the rights, privileges
          and voting powers of the holders of Common Units; but subject, in any
          event, to the following provisions:

          (i)  With respect to any Transaction, so long as the LTIP Units are
               treated in accordance with Section 8.8.F hereof, the consummation
               of such Transaction shall not be deemed to materially and
               adversely affect such rights, preferences, privileges or voting
               powers of the LTIP Units or the LTIP Unitholders as such; and

          (ii) Any creation or issuance of any Partnership Units or of any class
               or series of Partnership Interest including without limitation
               additional Common Units, LTIP Units or Preferred Units, whether
               ranking senior to, junior to, or on a parity with the LTIP Units
               with respect to distributions and the distribution of assets upon
               liquidation, dissolution or winding up, shall not be deemed to
               materially and adversely affect such rights, preferences,
               privileges or voting powers of the LTIP Units or the LTIP
               Unitholders as such.

               The foregoing voting provisions will not apply if, at or prior to
          the time when the act with respect to which such vote would otherwise
          be required will be effected, all outstanding LTIP Units shall have
          been converted into Common Units.

6.   CONFIRMATION OF AGREEMENT.  Except as modified herein, all terms and
     conditions of the Partnership Agreement shall remain in full force and
     effect.

                                  [End of Text]

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     IN WITNESS WHEREOF, the General Partner has executed this Amendment as of
the date first written above.

                                    BOSTON PROPERTIES, INC., as general partner
                                    of Boston Properties Limited Partnership


                                    By:     /s/ William J. Wedge
                                         ---------------------------------------

                                    Name:   William J. Wedge
                                         --------------------------------------

                                    Title:  Senior Vice President
                                          -------------------------------------

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                                    Exhibit A
     to _____________________ Amendment to Agreement of Limited Partnership

                    NOTICE OF ELECTION BY PARTNER TO CONVERT
                          LTIP UNITS INTO COMMON UNITS

     The undersigned LTIP Unitholder hereby irrevocably (i) elects to convert
the number of LTIP Units in Boston Properties Limited Partnership (the
"PARTNERSHIP") set forth below into Common Units in accordance with the terms of
the Second Amended and Restated Agreement of Limited Partnership of the
Partnership, as amended; and (ii) directs that any cash in lieu of Common Units
that may be deliverable upon such conversion be delivered to the address
specified below. The undersigned hereby represents, warrants, and certifies that
the undersigned (a) has title to such LTIP Units, free and clear of the rights
or interests of any other person or entity other than the Partnership; (b) has
the full right, power, and authority to cause the conversion of such LTIP Units
as provided herein; and (c) has obtained the consent or approval of all persons
or entities, if any, having the right to consent or approve such conversion.

Name of LTIP Unitholder:
                        --------------------------------------------------------
                       (Please Print: Exact Name as Registered with Partnership)

Number of LTIP Units to be Converted:
                                     ----------------------

Date of this Notice:
                    ---------------------------------------

  ------------------------------------------------------------------------------
  (Signature of Limited Partner: Sign Exact Name as Registered with Partnership)

  ------------------------------------------------------------------------------
  (Street Address)

  ------------------------------------------------------------------------------
  (City)                           (State)                            (Zip Code)

  Signature Guaranteed by:
                          ------------------------------------------------------

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                                    Exhibit B
     to _____________________ Amendment to Agreement of Limited Partnership

              NOTICE OF ELECTION BY PARTNERSHIP TO FORCE CONVERSION
                         OF LTIP UNITS INTO COMMON UNITS

     Boston Properties Limited Partnership (the "PARTNERSHIP") hereby
irrevocably (i) elects to cause the number of LTIP Units held by the LTIP
Unitholder set forth below to be converted into Common Units in accordance with
the terms of the Second Amended and Restated Agreement of Limited Partnership of
the Partnership, as amended

Name of LTIP Unitholder:________________________________________________________
                       (Please Print: Exact Name as Registered with Partnership)

Number of LTIP Units to be Converted:______________________

Date of this Notice:_______________________________________


LIBC/1591198.6