EXHIBIT 12 — STATEMENT RE: COMPUTATION OF RATIO
OF EARNINGS TO FIXED CHARGES
AND RATIO OF EARNINGS TO COMBINED FIXED CHARGES

LIBERTY PROPERTY TRUST / LIBERTY PROPERTY LIMITED PARTNERSHIP
(Amounts in thousands except ratio amounts)

	Nine months ended		Year ended December 31,
	September 30, 2004		2003		2002		2001		2000		1999
Earnings before fixed charges:
Income before allocation of minority interest and income from investment in unconsolidated subsidiaries(1)	$	125,259	$	171,724	$	171,478	$	182,378	$	178,570	$	153,125
Add:     Interest expense		88,603		119,743		111,890		105,722		102,486		93,003
Depreciation expense on cap’d interest		2,548		3,140		2,944		2,311		1,809		1,396
Amortization of deferred financing costs		3,351		4,013		3,979		4,015		4,066		4,951
Earnings before fixed charges	$	219,761	$	298,620	$	290,291	$	294,426	$	286,931	$	252,475
Fixed charges:
Interest expense	$	88,603	$	119,743	$	111,890	$	105,722	$	102,486	$	93,003
Amortization of deferred financing charges		3,351		4,013		3,979		4,015		4,066		4,951
Capitalized interest		9,693		10,947		16,498		22,347		17,784		15,288
Fixed charges		101,647		134,703		132,367		132,084		124,336		113,242
Preferred share distributions		—		—		7,242		11,000		11,000		11,000
Preferred unit distributions		9,168		12,416		11,619		10,612		10,070		3,783
Combined fixed charges	$	110,815	$	147,119	$	151,228	$	153,696	$	145,406	$	128,025
Ratio of earnings to fixed charges		2.16		2.22		2.19		2.23		2.31		2.23
Ratio of earnings to combined fixed charges		1.98		2.03		1.92		1.92		1.97		1.97

(1) Amounts for the years ended December 31, 2003, 2002, 2001, 2000, and 1999 have been reclassified to present properties that have been sold during 2004 consistent with the presentation for the period ended September 30, 2004. As a result, operations have been reclassified to discontinued operations from continuing operations for all periods presented.