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v3.25.3

Stock Option and Incentive Plan Stock and Units (Narrative) (Details) |  |  | 3 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Jan. 31, 2025 USD ($) shares | Jan. 22, 2025 USD ($) shares | Sep. 30, 2025 USD ($) shares | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) $ / shares shares | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($) shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Shares issued |  |  |  | 158,479,314 |  | 158,479,314 |  | 158,253,895
Stock based compensation expense | $ |  |  |  | $ 4,400,000 | $ 4,000,000 | $ 39,000,000 | $ 38,500,000 |
Common Stock, Value, Issued | $ |  |  |  | 1,584,000 |  | 1,584,000 |  | $ 1,582,000
Stock Issued During Period, Value, Restricted Stock Award, Gross | $ |  |  |  |  |  | $ 4,000,000 |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  | 55,571 |  |
LTIP Units [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Shares Issued, Value, Share-Based Payment Arrangement, before Forfeiture | $ |  |  |  |  |  | $ 27,000,000 |  |
Unvested Restricted stock and LTIP Units [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Unrecognized compensation expenses | $ |  |  |  | $ 24,300,000 |  | $ 24,300,000 |  |
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Annual Installments for Vesting |  |  |  |  |  | 4 |  |
MYLTIP 2025 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting Period |  |  | 3 years |  |  |  |  |
Value of MYLTIP Awards | $ |  |  | $ 12,700,000 |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Terms of Award |  |  | The 2025 MYLTIP awards consist of three components. Two of the components are each weighted 40% and utilize BXP’s TSR and BXP’s diluted Funds from Operations (“FFO”) per share growth, respectively, over a three-year measurement period as the performance metrics and the third component, weighted 20%, utilizes an average leverage ratio as the performance metric. |  |  |  |  |
MYLTIP 2022 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Vesting Period |  | 3 years |  |  |  |  |  |
Final awards percentage of target |  | 59.00% |  |  |  |  |  |
Value of MYLTIP Awards | $ |  | $ 5,400,000 |  |  |  |  |  |
Boston Properties Limited Partnership | LTIP Units [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Number of shares issued |  |  |  |  |  | 406,646 |  |
Noncontrolling Interest, Outstanding | [1] |  |  | 2,702,590 |  | 2,702,590 |  |
Boston Properties Limited Partnership | MYLTIP 2025 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Noncontrolling Interest, Outstanding |  |  |  | 354,940 |  | 354,940 |  |
Common stock available for issuance, target |  |  | 177,470 |  |  |  |  |
Boston Properties Limited Partnership | MYLTIP 2025 | Maximum [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Common stock available for issuance |  |  | 354,940 |  |  |  |  |
Boston Properties Limited Partnership | MYLTIP 2025 | Minimum [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Common stock available for issuance |  |  | 0 |  |  |  |  |
Boston Properties Limited Partnership | MYLTIP 2022 |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Forfeitures, in units |  | 177,919 |  |  |  |  |  |
Unvested MYLTIP Units [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Unrecognized compensation expenses | $ |  |  |  | $ 700,000 |  | $ 700,000 |  |
Weighted-average period (years) |  |  |  |  |  | 2 years 3 months 18 days |  |
LTIP and MYLTIP Units [Member] |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |
Employee and director payment per share (in dollars per share) | $ / shares |  |  |  |  |  | $ 0.25 |  |
[1] | Includes 655,534 LTIP Units earned by employees under the Company’s multi-year long-term incentive awards granted between 2012 and 2022 (i.e., 2012 OPP and 2013 - 2022 MYLTIP awards).

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