EXHIBIT 12.1

BOSTON PROPERTIES LIMITED PARTNERSHIP

CALCULATION OF RATIOS OF EARNINGS TO FIXED CHARGES

CALCULATION OF RATIOS OF EARNINGS TO COMBINED FIXED CHARGES AND

PREFERRED DISTRIBUTIONS

Boston Properties Limited Partnership’s ratios of earnings to fixed charges and ratios of earnings to combined fixed charges and preferred distributions for the nine months ended September 30, 2013 and the five years ended December 31, 2012 were as follows:

	Nine Months Ended September  30,			Year Ended December 31,
	2013			2012			2011			2010			2009			2008
	(unaudited)
	(dollars in thousands)
Earnings:
Add:
Income from continuing operations before income (loss) from unconsolidated joint ventures	$	177,847		$	253,327		$	234,272		$	157,600		$	257,599		$	287,909
Gains on sales of real estate		—			—			—			2,734			11,760			33,340
Amortization of interest capitalized		4,099			5,278			4,188			2,660			2,498			2,315
Distributions from unconsolidated joint ventures		14,607			20,565			22,451			10,733			6,676			5,988
Fixed charges (see below)		381,008			465,586			446,633			419,881			372,465			341,203
Subtract:
Interest capitalized		(50,252	)		(44,278	)		(48,178	)		(40,981	)		(48,816	)		(46,286	)
Total earnings	$	527,309		$	700,478		$	659,366		$	552,627		$	602,182		$	624,469
Fixed charges:
Interest expensed	$	325,746		$	413,564		$	394,131		$	378,079		$	322,833		$	294,126
Interest capitalized		50,252			44,278			48,178			40,981			48,816			46,286
Portion of rental expense representative of the interest factor		5,010			7,744			4,324			821			816			791
Total fixed charges	$	381,008		$	465,586		$	446,633		$	419,881		$	372,465		$	341,203
Preferred distributions		8,796			3,497			3,339			3,343			3,594			4,226
Total combined fixed charges and preferred distributions	$	389,804		$	469,083		$	449,972		$	423,224		$	376,059		$	345,429
Ratio of earnings to fixed charges		1.38			1.50			1.48			1.32			1.62			1.83
Ratio of earnings to combined fixed charges and preferred distributions		1.35			1.49			1.47			1.31			1.60			1.81