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                                                                    EXHIBIT 32.1


CERTIFICATION PURSUANT TO 18 U.S.C. SECTION 1350, AS ADOPTED PURSUANT TO SECTION
906 OF THE SARBANES-OXLEY ACT OF 2002

The undersigned officer of Boston Properties, Inc. (the "Company") hereby
certifies to my knowledge that the Company's quarterly report on Form 10-Q for
the quarterly period ended June 30, 2003 (the "Report"), as filed with the
Securities and Exchange Commissions on the date hereof, fully complies with the
requirements of Section 13(a) or 15(d), as applicable, of the Securities
Exchange Act of 1934, as amended, and that the information contained in the
Report fairly presents, in all material respects, the financial condition and
results of operations of the Company. This certification shall not be deemed
"filed" for any purpose, nor shall it be deemed to be incorporated by reference
into any filing under the Securities Act of 1933 or the Securities Exchange Act
of 1934 regardless of any general incorporation language in such filing.

Date:  August 14, 2003


                                                /s/ Edward H. Linde
                                                ------------------------------
                                                Edward H. Linde
                                                Chief Executive Officer