Unsecured Exchangeable Senior Notes (Tables)

12 Months Ended

Dec. 31, 2011

Unsecured Exchangeable Senior Notes [Abstract]

Schedule of Unsecured Exchangeable Senior Notes

	Coupon/ Stated Rate			Effective Rate(1)			Exchange Rate			Principal Amount			First Optional Redemption Date by Company	Maturity Date
3.625% Exchangeable Senior Notes		3.625	%		4.037	%		8.5051	(2)	$	747,500		N/A	February 15, 2014
2.875% Exchangeable Senior Notes		2.875	%		3.462	%		7.0430	(3)		576,194		February 20, 2012(4)	February 15, 2037
3.750% Exchangeable Senior Notes		3.750	%		3.787	%		10.0066	(5)		450,000		May 18, 2013(6)	May 15, 2036
Total principal											1,773,694
Net unamortized discount											(3,462	)
Adjustment for the equity component allocation, net of accumulated amortization											(54,547	)
Total										$	1,715,685

(1) Yield on issuance date including the effects of discounts on the notes but excluding the effects of the adjustment for the equity component allocation.

(2) The initial exchange rate is 8.5051 shares per $1,000 principal amount of the notes (or an initial exchange price of approximately $117.58 per share of Boston Properties, Inc.'s common stock). In addition, the Company entered into capped call transactions with affiliates of certain of the initial purchasers, which are intended to reduce the potential dilution upon future exchange of the notes. The capped call transactions were intended to increase the effective exchange price to the Company of the notes from $117.58 to approximately $137.17 per share (subject to adjustment), representing an overall effective premium of approximately 40% over the closing price on August 13, 2008 of $97.98 per share of Boston Properties, Inc.'s common stock. The net cost of the capped call transactions was approximately $44.4 million. As of December 31, 2011, the effective exchange price was $135.25 per share.

(3) In connection with the special distribution of $5.98 per share of Boston Properties, Inc.'s common stock declared on December 17, 2007, the exchange rate was adjusted from 6.6090 to 7.0430 shares per $1,000 principal amount of notes effective as of December 31, 2007, resulting in an exchange price of approximately $141.98 per share of Boston Properties, Inc.'s common stock (See Note 20).

(4) Holders may require the Operating Partnership to repurchase the notes for cash on February 15, 2012, 2017, 2022, 2027 and 2032 and at any time prior to their maturity upon a fundamental change, in each case at a price equal to 100% of the principal amount of the notes being repurchased plus any accrued and unpaid interest up to, but excluding, the repurchase date. The Operating Partnership repurchased/redeemed the notes for cash in February 2012 at a price equal to 100% of the principal amount of the notes being repurchased/redeemed plus any accrued and unpaid interest up to, but excluding, the repurchase/redemption date (See Note 20).

(5) In connection with the special distribution of $5.98 per share of Boston Properties, Inc.'s common stock declared on December 17, 2007, the exchange rate was adjusted from 9.3900 to 10.0066 shares per $1,000 principal amount of notes effective as of December 31, 2007, resulting in an exchange price of approximately $99.93 per share of Boston Properties, Inc.'s common stock.

(6) Holders may require the Operating Partnership to repurchase the notes for cash on May 18, 2013 and May 15, 2016, 2021, 2026 and 2031 and at any time prior to their maturity upon a fundamental change, in each case at a price equal to 100% of the principal amount of the notes being repurchased plus any accrued and unpaid interest up to, but excluding, the repurchase date.