Schedule III - Real Estate and Accumulated Depreciation

12 Months Ended

Dec. 31, 2024

SEC Schedule, 12-28, Real Estate Companies, Investment in Real Estate and Accumulated Depreciation Disclosure [Abstract]

Schedule III-Real Estate and Accumulated Depreciation


				Initial Cost						Gross Amounts Carried At Close of Period
Property (Type) (1)	Location	Encumbrances (2)		Land		Building and Land Improvements		Costs Capitalized Subsequent to Acquisition		Land		Building and Land Improvements		Total (3)		Accumulated Depreciation (4)		Year Built or Renovated	Date Acquired (5)
100 Light Street (O)	Baltimore, MD	$	—	$	6,720	$	31,215	$	31,887	$	6,720	$	63,102	$	69,822	$	(39,347)	1973/2011	8/7/2015
100 Secured Gateway (O)	Huntsville, AL	—		—		71,180		108		—		71,288		71,288		(7,700)		2020	3/23/2010
1000 Redstone Gateway (O)	Huntsville, AL	—		—		20,533		241		—		20,774		20,774		(6,092)		2013	3/23/2010
1100 Redstone Gateway (O)	Huntsville, AL	—		—		19,593		4,359		—		23,952		23,952		(5,701)		2014	3/23/2010
114 National Business Parkway (O)	Annapolis Junction, MD	—		364		3,109		427		364		3,536		3,900		(1,985)		2002	6/30/2000
1200 Redstone Gateway (O)	Huntsville, AL	—		—		22,389		11,794		—		34,183		34,183		(7,987)		2013	3/23/2010
1201 M Street SE (O)	Washington, DC	—		—		49,775		11,615		—		61,390		61,390		(27,471)		2001	9/28/2010
1201 Winterson Road (O)	Linthicum, MD	—		2,130		17,769		1,197		2,130		18,966		21,096		(7,305)		1985/2017	4/30/1998
1220 12th Street SE (O)	Washington, DC	—		—		42,464		11,996		—		54,460		54,460		(25,127)		2003	9/28/2010
1243 Winterson Road (L)	Linthicum, MD	—		630		—		—		630		—		630		—		(6)	12/19/2001
131 National Business Parkway (O)	Annapolis Junction, MD	—		1,906		7,623		6,876		1,906		14,499		16,405		(10,092)		1990	9/28/1998
132 National Business Parkway (O)	Annapolis Junction, MD	—		2,917		12,259		4,996		2,917		17,255		20,172		(12,210)		2000	5/28/1999
133 National Business Parkway (O)	Annapolis Junction, MD	—		2,517		10,068		7,034		2,517		17,102		19,619		(12,476)		1997	9/28/1998
134 National Business Parkway (O)	Annapolis Junction, MD	—		3,684		7,517		5,924		3,684		13,441		17,125		(10,100)		1999	11/13/1998
1340 Ashton Road (O)	Hanover, MD	—		905		3,620		2,743		905		6,363		7,268		(4,066)		1989	4/28/1999
13450 Sunrise Valley Drive (O)	Herndon, VA	—		1,386		5,576		8,433		1,386		14,009		15,395		(7,632)		1998	7/25/2003
13454 Sunrise Valley Drive (O)	Herndon, VA	—		2,847		11,986		14,962		2,847		26,948		29,795		(15,830)		1998	7/25/2003
135 National Business Parkway (O)	Annapolis Junction, MD	—		2,484		9,750		7,302		2,484		17,052		19,536		(12,646)		1998	12/30/1998
1362 Mellon Road (O)	Hanover, MD	—		950		3,864		3,389		950		7,253		8,203		(2,606)		2006	2/10/2006
13857 McLearen Road (O)	Herndon, VA	—		3,507		30,177		6,413		3,507		36,590		40,097		(17,042)		2007	7/11/2012
140 National Business Parkway (O)	Annapolis Junction, MD	—		3,407		24,167		2,995		3,407		27,162		30,569		(13,892)		2003	12/31/2003
141 National Business Parkway (O)	Annapolis Junction, MD	—		2,398		9,538		7,169		2,398		16,707		19,105		(10,822)		1990	9/28/1998
14280 Park Meadow Drive (O)	Chantilly, VA	—		3,731		15,953		7,395		3,731		23,348		27,079		(13,205)		1999	9/29/2004
1460 Dorsey Road (L)	Hanover, MD	—		1,577		187		—		1,577		187		1,764		—		(6)	2/28/2006
14840 Conference Center Drive (O)	Chantilly, VA	—		1,572		8,175		5,813		1,572		13,988		15,560		(9,477)		2000	7/25/2003
14850 Conference Center Drive (O)	Chantilly, VA	—		1,615		8,358		8,355		1,615		16,713		18,328		(9,584)		2000	7/25/2003
14900 Conference Center Drive (O)	Chantilly, VA	—		3,436		14,402		10,714		3,436		25,116		28,552		(16,346)		1999	7/25/2003
1501 South Clinton Street (O)	Baltimore, MD	—		13,137		20,753		47,566		13,137		68,319		81,456		(40,781)		2006	10/27/2009
15049 Conference Center Drive (O)	Chantilly, VA	—		4,415		20,365		18,568		4,415		38,933		43,348		(26,087)		1997	8/14/2002
15059 Conference Center Drive (O)	Chantilly, VA	—		5,753		13,615		9,591		5,753		23,206		28,959		(13,122)		2000	8/14/2002
1550 West Nursery Road (O)	Linthicum, MD	—		14,071		16,930		—		14,071		16,930		31,001		(7,783)		2009	10/28/2009
1560 West Nursery Road (O)	Linthicum, MD	—		1,441		113		—		1,441		113		1,554		(30)		2014	10/28/2009
1610 West Nursery Road (O)	Linthicum, MD	—		259		246		—		259		246		505		(48)		2016	4/30/1998
1616 West Nursery Road (O)	Linthicum, MD	—		393		3,323		75		393		3,398		3,791		(629)		2017	4/30/1998
1622 West Nursery Road (O)	Linthicum, MD	—		393		2,542		—		393		2,542		2,935		(500)		2016	4/30/1998
16442 Commerce Drive (O)	Dahlgren, VA	—		613		2,582		1,143		613		3,725		4,338		(2,358)		2002	12/21/2004
16480 Commerce Drive (O)	Dahlgren, VA	—		1,856		7,425		3,736		1,856		11,161		13,017		(6,049)		2000	12/28/2004


			Initial Cost			Gross Amounts Carried At Close of Period
Property (Type) (1)	Location	Encumbrances (2)	Land	Building and Land Improvements	Costs Capitalized Subsequent to Acquisition	Land	Building and Land Improvements	Total (3)	Accumulated Depreciation (4)	Year Built or Renovated	Date Acquired (5)
16501 Commerce Drive (O)	Dahlgren, VA	—	522	2,090	1,674	522	3,764	4,286	(1,924)	2002	12/21/2004
16539 Commerce Drive (O)	Dahlgren, VA	—	688	2,860	2,481	688	5,341	6,029	(3,442)	1990	12/21/2004
16541 Commerce Drive (O)	Dahlgren, VA	—	773	3,094	2,715	773	5,809	6,582	(3,801)	1996	12/21/2004
16543 Commerce Drive (O)	Dahlgren, VA	—	436	1,742	906	436	2,648	3,084	(1,632)	2002	12/21/2004
1751 Pinnacle Drive (O)	McLean, VA	—	4,762	26,046	34,717	4,762	60,763	65,525	(50,069)	1989/1995	9/23/2004
1753 Pinnacle Drive (O)	McLean, VA	—	3,729	21,500	28,740	3,729	50,240	53,969	(35,257)	1976/2004	9/23/2004
206 Research Boulevard (O)	Aberdeen, MD	—	—	—	—	—	—	—	—	2012	9/14/2007
209 Research Boulevard (O)	Aberdeen, MD	—	134	1,711	895	134	2,606	2,740	(1,016)	2010	9/14/2007
210 Research Boulevard (O)	Aberdeen, MD	—	113	1,402	593	113	1,995	2,108	(813)	2010	9/14/2007
2100 L Street (O)	Washington, DC	—	41,935	74,965	—	41,935	74,965	116,900	(8,426)	2020	8/11/2015
2100 Rideout Road (O)	Huntsville, AL	—	—	7,336	3,583	—	10,919	10,919	(3,759)	2016	3/23/2010
22289 Exploration Drive (O)	Lexington Park, MD	—	1,422	5,719	2,657	1,422	8,376	9,798	(5,120)	2000	3/24/2004
22299 Exploration Drive (O)	Lexington Park, MD	—	1,278	5,791	3,085	1,278	8,876	10,154	(5,966)	1998	3/24/2004
22300 Exploration Drive (O)	Lexington Park, MD	—	1,094	5,038	3,061	1,094	8,099	9,193	(5,307)	1997	11/9/2004
22309 Exploration Drive (O)	Lexington Park, MD	—	2,160	10,419	12,011	2,160	22,430	24,590	(11,076)	1984/1997	3/24/2004
23535 Cottonwood Parkway (O)	California, MD	—	692	3,051	706	692	3,757	4,449	(2,690)	1984	3/24/2004
250 W Pratt St (O)	Baltimore, MD	—	4,704	21,487	23,603	4,704	45,090	49,794	(27,845)	1985	3/19/2015
2600 Park Tower Drive (O)	Vienna, VA	—	20,263	34,443	17,535	20,263	51,978	72,241	(13,133)	1999	4/15/2015
2691 Technology Drive (O)	Annapolis Junction, MD	—	2,098	17,334	9,191	2,098	26,525	28,623	(14,958)	2005	5/26/2000
2701 Technology Drive (O)	Annapolis Junction, MD	—	1,737	15,266	8,523	1,737	23,789	25,526	(15,503)	2001	5/26/2000
2711 Technology Drive (O)	Annapolis Junction, MD	—	2,251	21,611	7,198	2,251	28,809	31,060	(17,607)	2002	11/13/2000
2720 Technology Drive (O)	Annapolis Junction, MD	—	3,863	29,272	3,257	3,863	32,529	36,392	(17,427)	2004	1/31/2002
2721 Technology Drive (O)	Annapolis Junction, MD	—	4,611	14,597	5,706	4,611	20,303	24,914	(12,575)	2000	10/21/1999
2730 Hercules Road (O)	Annapolis Junction, MD	—	8,737	31,612	10,659	8,737	42,271	51,008	(27,592)	1990	9/28/1998
30 Light Street (O)	Baltimore, MD	—	—	2,501	762	—	3,263	3,263	(3,093)	2009	8/7/2015
300 Secured Gateway (O)	Huntsville, AL	—	—	64,356	32	—	64,388	64,388	(1,986)	2023	3/23/2010
300 Sentinel Drive (O)	Annapolis Junction, MD	—	1,517	59,165	3,702	1,517	62,867	64,384	(24,050)	2009	11/14/2003
302 Sentinel Drive (O)	Annapolis Junction, MD	—	2,648	29,687	8,015	2,648	37,702	40,350	(15,247)	2007	11/14/2003
304 Sentinel Drive (O)	Annapolis Junction, MD	—	3,411	24,917	5,353	3,411	30,270	33,681	(15,864)	2005	11/14/2003
306 Sentinel Drive (O)	Annapolis Junction, MD	—	3,260	22,592	3,901	3,260	26,493	29,753	(12,963)	2006	11/14/2003

308 Sentinel Drive (O)	Annapolis Junction, MD	—	1,422	26,208	2,365	1,422	28,573	29,995	(10,521)	2010	11/14/2003
310 Sentinel Way (O)	Annapolis Junction, MD	—	2,372	50,750	706	2,372	51,456	53,828	(9,550)	2016	11/14/2003
310 The Bridge Street (O)	Huntsville, AL	—	261	26,530	7,230	261	33,760	34,021	(15,607)	2009	8/9/2011
312 Sentinel Way (O)	Annapolis Junction, MD	—	3,138	27,797	—	3,138	27,797	30,935	(7,169)	2014	11/14/2003
314 Sentinel Way (O)	Annapolis Junction, MD	—	1,254	7,741	—	1,254	7,741	8,995	(2,180)	2008	11/14/2003
316 Sentinel Way (O)	Annapolis Junction, MD	—	2,748	38,156	279	2,748	38,435	41,183	(12,332)	2011	11/14/2003
318 Sentinel Way (O)	Annapolis Junction, MD	—	2,185	28,426	568	2,185	28,994	31,179	(13,784)	2005	11/14/2003


			Initial Cost			Gross Amounts Carried At Close of Period
Property (Type) (1)	Location	Encumbrances (2)	Land	Building and Land Improvements	Costs Capitalized Subsequent to Acquisition	Land	Building and Land Improvements	Total (3)	Accumulated Depreciation (4)	Year Built or Renovated	Date Acquired (5)
320 Sentinel Way (O)	Annapolis Junction, MD	—	2,067	21,623	156	2,067	21,779	23,846	(9,301)	2007	11/14/2003
322 Sentinel Way (O)	Annapolis Junction, MD	—	2,605	22,827	1,901	2,605	24,728	27,333	(11,611)	2006	11/14/2003
324 Sentinel Way (O)	Annapolis Junction, MD	—	1,656	23,018	62	1,656	23,080	24,736	(8,271)	2010	6/29/2006
340th Trail (L)	Van Meter, IA	—	32,852	419	—	32,852	419	33,271	—	(6)	9/27/2024
3900 Rogers Road (O)	San Antonio, TX	—	2,932	14,101	—	2,932	14,101	17,033	(88)	2005	9/26/2024
400 National Business Parkway (O)	Annapolis Junction, MD	—	—	41,547	—	—	41,547	41,547	—	(7)	6/29/2006
4000 Market Street (O)	Huntsville, AL	5,835	—	9,198	2,162	—	11,360	11,360	(1,666)	2018	3/23/2010
410 National Business Parkway (O)	Annapolis Junction, MD	—	1,831	23,257	2,997	1,831	26,254	28,085	(9,010)	2012	6/29/2006
4100 Market Street (O)	Huntsville, AL	5,080	—	8,046	26	—	8,072	8,072	(1,118)	2019	3/23/2010
420 National Business Parkway (O)	Annapolis Junction, MD	—	2,370	31,607	4,364	2,370	35,971	38,341	(8,289)	2013	6/29/2006
430 National Business Parkway (O)	Annapolis Junction, MD	—	1,852	21,563	4,562	1,852	26,125	27,977	(8,672)	2011	6/29/2006
44408 Pecan Court (O)	California, MD	—	817	1,583	1,861	817	3,444	4,261	(2,577)	1986	3/24/2004
44414 Pecan Court (O)	California, MD	—	405	1,619	1,229	405	2,848	3,253	(2,161)	1986	3/24/2004
44417 Pecan Court (O)	California, MD	—	434	3,822	315	434	4,137	4,571	(2,774)	1989/2015	3/24/2004
44420 Pecan Court (O)	California, MD	—	344	890	418	344	1,308	1,652	(792)	1989	11/9/2004
44425 Pecan Court (O)	California, MD	—	1,309	3,506	2,697	1,309	6,203	7,512	(4,564)	1997	5/5/2004
45310 Abell House Lane (O)	California, MD	—	2,272	13,808	2,884	2,272	16,692	18,964	(5,819)	2011	8/30/2010
4600 River Road (O)	College Park, MD	—	—	27,338	123	—	27,461	27,461	(2,376)	2020	1/29/2008
46579 Expedition Drive (O)	Lexington Park, MD	—	1,406	5,796	3,016	1,406	8,812	10,218	(5,497)	2002	3/24/2004
46591 Expedition Drive (O)	Lexington Park, MD	—	1,200	7,199	5,164	1,200	12,363	13,563	(6,500)	2005	3/24/2004
4851 Stonecroft Boulevard (O)	Chantilly, VA	—	1,878	11,558	1,355	1,878	12,913	14,791	(5,991)	2004	8/14/2002
5300 Redstone Gateway (O)	Huntsville, AL	—	—	19,001	—	—	19,001	19,001	(392)	2024	3/23/2010
540 National Business Parkway (O)	Annapolis Junction, MD	—	2,035	35,639	41	2,035	35,680	37,715	(5,925)	2017	6/29/2006
550 National Business Parkway (O)	Annapolis Junction, MD	—	2,678	44,027	—	2,678	44,027	46,705	(1,298)	2023	6/29/2006
5520 Research Park Drive (O)	Catonsville, MD	—	—	20,072	2,376	—	22,448	22,448	(9,156)	2009	4/4/2006
5522 Research Park Drive (O)	Catonsville, MD	—	—	4,550	985	—	5,535	5,535	(2,425)	2007	3/8/2006
560 National Business Parkway (O)	Annapolis Junction, MD	—	2,193	55,484	—	2,193	55,484	57,677	(3,047)	2022	6/29/2006
5801 University Research Court (O)	College Park, MD	10,400	—	17,431	162	—	17,593	17,593	(3,158)	2018	1/29/2008
5825 University Research Court (O)	College Park, MD	18,067	—	22,771	3,675	—	26,446	26,446	(10,782)	2008	1/29/2008
5850 University Research Court (O)	College Park, MD	19,114	—	31,906	1,112	—	33,018	33,018	(12,415)	2008	1/29/2008
6000 Redstone Gateway (O)	Huntsville, AL	—	—	8,542	35	—	8,577	8,577	(852)	2020	3/23/2010
610 Guardian Way (O)	Annapolis Junction, MD	—	7,636	54,053	—	7,636	54,053	61,689	(4,263)	2021	6/29/2006
6200 Redstone Gateway (O)	Huntsville, AL	—	—	51,343	—	—	51,343	51,343	(2,849)	2022	3/23/2010
6700 Alexander Bell Drive (O)	Columbia, MD	—	1,755	7,019	11,262	1,755	18,281	20,036	(11,758)	1988	5/14/2001
6708 Alexander Bell Drive (O)	Columbia, MD	—	897	12,693	1,624	897	14,317	15,214	(5,801)	1988/2016	5/14/2001
6711 Columbia Gateway Drive (O)	Columbia, MD	—	2,683	23,239	3,413	2,683	26,652	29,335	(12,411)	2006-2007	9/28/2000
6716 Alexander Bell Drive (O)	Columbia, MD	—	1,242	4,969	8,321	1,242	13,290	14,532	(7,669)	1990	12/31/1998


			Initial Cost			Gross Amounts Carried At Close of Period
Property (Type) (1)	Location	Encumbrances (2)	Land	Building and Land Improvements	Costs Capitalized Subsequent to Acquisition	Land	Building and Land Improvements	Total (3)	Accumulated Depreciation (4)	Year Built or Renovated	Date Acquired (5)
6721 Columbia Gateway Drive (O)	Columbia, MD	—	1,753	34,090	14,624	1,753	48,714	50,467	(17,021)	2009	9/28/2000
6724 Alexander Bell Drive (O)	Columbia, MD	—	449	5,039	2,698	449	7,737	8,186	(4,923)	2001	5/14/2001
6731 Columbia Gateway Drive (O)	Columbia, MD	—	2,807	19,098	7,035	2,807	26,133	28,940	(16,920)	2002	3/29/2000
6740 Alexander Bell Drive (O)	Columbia, MD	—	1,424	4,209	10,544	1,424	14,753	16,177	(4,110)	1992	12/31/1998
6741 Columbia Gateway Drive (O)	Columbia, MD	—	675	1,711	535	675	2,246	2,921	(855)	2008	9/28/2000
6750 Alexander Bell Drive (O)	Columbia, MD	—	1,263	12,461	6,070	1,263	18,531	19,794	(12,881)	2001	12/31/1998
6760 Alexander Bell Drive (O)	Columbia, MD	—	890	3,561	4,253	890	7,814	8,704	(5,817)	1991	12/31/1998
6841 Benjamin Franklin Drive (O)	Columbia, MD	—	5,429	2,534	1,697	5,429	4,231	9,660	(567)	2008	3/15/2024
6940 Columbia Gateway Drive (O)	Columbia, MD	—	3,545	9,916	13,156	3,545	23,072	26,617	(15,179)	1999	11/13/1998
6950 Columbia Gateway Drive (O)	Columbia, MD	—	3,596	28,278	3,223	3,596	31,501	35,097	(14,899)	1998/2019	10/22/1998
7000 Columbia Gateway Drive (O)	Columbia, MD	—	3,131	12,103	10,516	3,131	22,619	25,750	(14,394)	1999	5/31/2002
7000 Redstone Gateway (O)	Huntsville, AL	—	—	10,036	30	—	10,066	10,066	(458)	2022	3/23/2010
7005 Columbia Gateway Drive (L)	Columbia, MD	—	3,036	747	—	3,036	747	3,783	—	(6)	6/26/2014
7015 Albert Einstein Drive (O)	Columbia, MD	—	2,058	6,093	3,560	2,058	9,653	11,711	(6,068)	1999	12/1/2005
7061 Columbia Gateway Drive (O)	Columbia, MD	—	729	3,094	2,902	729	5,996	6,725	(4,125)	2000	8/30/2001
7063 Columbia Gateway Drive (O)	Columbia, MD	—	902	3,684	3,707	902	7,391	8,293	(5,314)	2000	8/30/2001
7065 Columbia Gateway Drive (O)	Columbia, MD	—	919	3,763	4,017	919	7,780	8,699	(5,221)	2000	8/30/2001
7067 Columbia Gateway Drive (O)	Columbia, MD	—	1,829	11,823	10,077	1,829	21,900	23,729	(12,159)	2001	8/30/2001
7100 Redstone Gateway (O)	Huntsville, AL	—	—	12,983	17	—	13,000	13,000	(1,164)	2021	3/23/2010
7125 Columbia Gateway Drive (O)	Columbia, MD	—	20,487	49,926	34,620	20,487	84,546	105,033	(38,340)	1973/1999	6/29/2006
7130 Columbia Gateway Drive (O)	Columbia, MD	—	1,350	4,359	3,187	1,350	7,546	8,896	(4,927)	1989	9/19/2005
7134 Columbia Gateway Drive (O)	Columbia, MD	—	704	4,700	837	704	5,537	6,241	(2,503)	1990/2016	9/19/2005
7138 Columbia Gateway Drive (O)	Columbia, MD	—	1,104	3,518	3,067	1,104	6,585	7,689	(4,841)	1990	9/19/2005
7142 Columbia Gateway Drive (O)	Columbia, MD	—	1,342	7,148	4,236	1,342	11,384	12,726	(5,690)	1994/2018	9/19/2005
7150 Columbia Gateway Drive (O)	Columbia, MD	—	1,032	3,429	1,824	1,032	5,253	6,285	(2,620)	1991	9/19/2005
7150 Riverwood Drive (O)	Columbia, MD	—	1,821	4,388	16,232	1,821	20,620	22,441	(4,463)	2000	1/10/2007
7160 Riverwood Drive (O)	Columbia, MD	—	2,732	7,006	4,609	2,732	11,615	14,347	(6,810)	2000	1/10/2007
7170 Riverwood Drive (O)	Columbia, MD	—	1,283	3,096	2,624	1,283	5,720	7,003	(3,387)	2000	1/10/2007
7175 Riverwood Drive (O)	Columbia, MD	—	1,788	7,269	57	1,788	7,326	9,114	(2,031)	1996/2013	7/27/2005
7200 Redstone Gateway (O)	Huntsville, AL	—	—	8,348	206	—	8,554	8,554	(2,273)	2013	3/23/2010
7200 Riverwood Drive (O)	Columbia, MD	—	4,089	22,630	5,908	4,089	28,538	32,627	(15,880)	1986	10/13/1998
7205 Riverwood Drive (O)	Columbia, MD	—	1,367	21,419	345	1,367	21,764	23,131	(6,129)	2013	7/27/2005
7272 Park Circle Drive (O)	Hanover, MD	—	1,479	6,300	5,263	1,479	11,563	13,042	(7,203)	1991/1996	1/10/2007
7318 Parkway Drive (O)	Hanover, MD	—	972	3,888	2,313	972	6,201	7,173	(3,808)	1984	4/16/1999
7400 Redstone Gateway (O)	Huntsville, AL	—	—	9,223	93	—	9,316	9,316	(2,231)	2015	3/23/2010
7467 Ridge Road (O)	Hanover, MD	—	1,565	3,116	7,729	1,565	10,845	12,410	(6,398)	1990	4/28/1999
7500 Advanced Gateway (O)	Huntsville, AL	—	—	18,665	97	—	18,762	18,762	(2,138)	2020	3/23/2010


			Initial Cost			Gross Amounts Carried At Close of Period
Property (Type) (1)	Location	Encumbrances (2)	Land	Building and Land Improvements	Costs Capitalized Subsequent to Acquisition	Land	Building and Land Improvements	Total (3)	Accumulated Depreciation (4)	Year Built or Renovated	Date Acquired (5)
7600 Advanced Gateway (O)	Huntsville, AL	—	—	13,752	28	—	13,780	13,780	(1,514)	2020	3/23/2010
7740 Milestone Parkway (O)	Hanover, MD	—	3,825	34,176	2,055	3,825	36,231	40,056	(13,148)	2009	7/2/2007
7770 Backlick Road (O)	Springfield, VA	—	6,387	78,892	2,185	6,387	81,077	87,464	(24,179)	2012	3/10/2010
7880 Milestone Parkway (O)	Hanover, MD	—	4,857	27,166	1,675	4,857	28,841	33,698	(7,003)	2015	9/17/2013
8000 Rideout Road (O)	Huntsville, AL	—	—	28,157	203	—	28,360	28,360	(1,964)	2021	3/23/2010
8100 Rideout Road (O)	Huntsville, AL	—	—	35,591	3	—	35,594	35,594	(544)	2024	3/23/2010
8200 Rideout Road (O)	Huntsville, AL	—	—	45,903	3	—	45,906	45,906	(3,138)	2022	3/23/2010
8300 Rideout Road (O)	Huntsville, AL	—	—	52,633	6	—	52,639	52,639	(3,672)	2022	3/23/2010
8600 Advanced Gateway (O)	Huntsville, AL	—	—	27,314	59	—	27,373	27,373	(2,765)	2020	3/23/2010
8621 Robert Fulton Drive (O)	Columbia, MD	—	2,317	12,642	8,084	2,317	20,726	23,043	(11,072)	2005-2006	6/10/2005
8661 Robert Fulton Drive (O)	Columbia, MD	—	1,510	3,764	3,443	1,510	7,207	8,717	(4,749)	2002	12/30/2003
8671 Robert Fulton Drive (O)	Columbia, MD	—	1,718	4,280	4,848	1,718	9,128	10,846	(6,173)	2002	12/30/2003
870 Elkridge Landing Road (O)	Linthicum, MD	—	2,003	9,442	10,600	2,003	20,042	22,045	(14,579)	1981	8/3/2001
8800 Redstone Gateway (O)	Huntsville, AL	11,260	—	18,470	12	—	18,482	18,482	(2,363)	2019	3/23/2010
891 Elkridge Landing Road (O)	Linthicum, MD	—	1,165	4,772	4,442	1,165	9,214	10,379	(6,534)	1984	7/2/2001
901 Elkridge Landing Road (O)	Linthicum, MD	—	1,156	4,437	8,106	1,156	12,543	13,699	(7,281)	1984	7/2/2001
911 Elkridge Landing Road (O)	Linthicum, MD	—	1,215	4,861	3,610	1,215	8,471	9,686	(6,123)	1985	4/30/1998
938 Elkridge Landing Road (O)	Linthicum, MD	—	922	4,748	1,533	922	6,281	7,203	(3,990)	1984	7/2/2001
939 Elkridge Landing Road (O)	Linthicum, MD	—	939	3,756	8,846	939	12,602	13,541	(6,868)	1983	4/30/1998
9700 Advanced Gateway (O)	Huntsville, AL	—	—	7,021	—	—	7,021	7,021	—	(7)	3/23/2010
Arundel Preserve (L)	Hanover, MD	—	13,352	10,799	—	13,352	10,799	24,151	—	(6)	7/2/2007
Canton Crossing Land (L)	Baltimore, MD	—	—	6,000	54	—	6,054	6,054	(54)	(6)	10/27/2009
Canton Crossing Util Distr Ctr (O)	Baltimore, MD	—	2,866	7,271	2,371	2,866	9,642	12,508	(8,142)	2006	10/27/2009
Columbia Gateway - Southridge (L)	Columbia, MD	—	6,387	3,725	—	6,387	3,725	10,112	—	(6)	9/20/2004
Dahlgren Technology Center (L)	Dahlgren, VA	—	978	178	—	978	178	1,156	—	(6)	3/16/2005
Expedition VII (O)	Lexington Park, MD	—	705	8,677	—	705	8,677	9,382	(542)	2022	3/24/2004
M Square Research Park (L)	College Park, MD	—	—	3,254	—	—	3,254	3,254	—	(6)	1/29/2008
MP 3 (O)	Northern Virginia	—	9,038	3,134	—	9,038	3,134	12,172	—	(7)	11/8/2018
National Business Park North (L)	Annapolis Junction, MD	—	15,554	25,740	—	15,554	25,740	41,294	—	(6)	6/29/2006
North Gate Business Park (L)	Aberdeen, MD	—	1,755	134	—	1,755	134	1,889	—	(6)	9/14/2007
NoVA Office A (O)	Chantilly, VA	—	2,096	46,849	—	2,096	46,849	48,945	(11,607)	2015	7/18/2002
NoVA Office B (O)	Chantilly, VA	—	739	38,376	—	739	38,376	39,115	(7,656)	2016	7/18/2002
NoVA Office C (O)	Chantilly, VA	—	7,751	85,774	—	7,751	85,774	93,525	(6,647)	2021	7/18/2002
NoVA Office D (O)	Chantilly, VA	—	6,587	40,559	—	6,587	40,559	47,146	(7,516)	2017	7/2/2013
Oak Grove A (O)	Northern Virginia	—	12,866	42,090	—	12,866	42,090	54,956	(4,333)	2020	11/1/2018
Oak Grove B (O)	Northern Virginia	—	12,866	41,621	—	12,866	41,621	54,487	(4,951)	2019	11/1/2018
Oak Grove C (O)	Northern Virginia	—	11,741	79,004	—	11,741	79,004	90,745	(5,300)	2022	11/1/2018


				Initial Cost						Gross Amounts Carried At Close of Period
Property (Type) (1)	Location	Encumbrances (2)		Land		Building and Land Improvements		Costs Capitalized Subsequent to Acquisition		Land		Building and Land Improvements		Total (3)		Accumulated Depreciation (4)		Year Built or Renovated	Date Acquired (5)
Oak Grove D (O)	Northern Virginia	—		11,741		78,391		—		11,741		78,391		90,132		(4,041)		2022	11/1/2018
Old Annapolis Road (O)	Columbia, MD	—		1,637		5,500		6,985		1,637		12,485		14,122		(6,974)		1974/1985	12/14/2000
Patriot Ridge (L)	Springfield, VA	—		18,517		14,650		—		18,517		14,650		33,167		—		(6)	3/10/2010
Project EL (O)	Confidential-USA	—		7,190		46,922		—		7,190		46,922		54,112		(4,055)		2021	1/20/2006
Project EX (O)	Confidential-USA	—		13,010		19,107		—		13,010		19,107		32,117		(2,754)		2018	7/16/2008
PS A (O)	Northern Virginia	—		4,078		54,767		—		4,078		54,767		58,845		(1,876)		2023	1/27/2005
PS B (O)	Northern Virginia	—		3,468		47,630		—		3,468		47,630		51,098		(1,238)		2023	1/27/2005
Redstone Gateway (L)	Huntsville, AL	—		—		36,810		66		—		36,876		36,876		(2)		(6)	3/23/2010
Sentry Gateway - T (O)	San Antonio, TX	—		14,020		38,804		13		14,020		38,817		52,837		(17,354)		1982/2008	3/30/2005
Sentry Gateway - V (O)	San Antonio, TX	—		—		1,066		—		—		1,066		1,066		(428)		2007	3/30/2005
Sentry Gateway - W (O)	San Antonio, TX	—		—		1,884		71		—		1,955		1,955		(755)		2009	3/30/2005
Sentry Gateway - X (O)	San Antonio, TX	—		1,964		21,178		53		1,964		21,231		23,195		(7,526)		2010	1/20/2006
Sentry Gateway - Y (O)	San Antonio, TX	—		1,964		21,298		73		1,964		21,371		23,335		(7,543)		2010	1/20/2006
Sentry Gateway - Z (O)	San Antonio, TX	—		1,964		30,573		—		1,964		30,573		32,537		(7,498)		2015	6/14/2005
Southpoint Phase 2 Bldg A (O)	Northern Virginia	—		4,404		56,542		—		4,404		56,542		60,946		(205)		2024	7/24/2019
Southpoint Phase 2 Bldg B (O)	Northern Virginia	—		3,752		2,850		—		3,752		2,850		6,602		—		(7)	7/24/2019

Westfields - Park Center (L)	Chantilly, VA	—		8,667		3,759		—		8,667		3,759		12,426		—		(6)	7/2/2013

Other Developments, including intercompany eliminations (V)	Various	—		—		1,140		258		—		1,398		1,398		(200)		Various	Various
		$	69,756	$	611,802	$	3,744,901	$	811,116	$	611,802	$	4,556,017	$	5,167,819	$	(1,537,293)

(1)A legend for the Property Type follows: (O) = Office or data center shell property; (L) = Land held or pre-development; and (V) = Various.

(2)Excludes our Revolving Credit Facility of $75.0 million, term loan facilities of $124.6 million, unsecured senior notes of $2.1 billion, unsecured notes payable of $251,000, and deferred financing costs, net of premiums, on the remaining loans of $155,000.

(3)The aggregate cost of these assets for federal income tax purposes was approximately $3.9 billion as of December 31, 2024.

(4)The estimated lives over which depreciation is recognized follow: Building and land improvements: 10-40 years; and tenant improvements: related lease terms.

(5)The acquisition date of multi-parcel properties reflects the date of the earliest parcel acquisition. The acquisition date of properties owned through real estate joint ventures reflects the date of the formation of the joint venture.

(6)Held as of December 31, 2024.

(7)Under development as of December 31, 2024.

The following table summarizes our changes in cost of properties for the years ended December 31, 2024, 2023 and 2022 (in thousands):


	2024		2023		2022
Beginning balance	$	4,903,840	$	4,986,537	$	4,959,709
Acquisitions of operating properties (1)	24,996		—		—
Improvements and other additions	239,096		333,081		350,702
Sales (2)	—		(162,981)		(323,874)
Impairments (3)	—		(252,797)		—

Other dispositions	(113)		—		—

Ending balance	$	5,167,819	$	4,903,840	$	4,986,537

The following table summarizes our changes in accumulated depreciation for the same time periods (in thousands):
	2024		2023		2022
Beginning balance	$	1,400,162	$	1,273,448	$	1,234,908
Depreciation expense	137,224		132,728		124,803
Sales (2)	—		(6,014)		(86,263)


Other dispositions	(93)		—		—
Ending balance	$	1,537,293	$	1,400,162	$	1,273,448

(1)Includes acquisitions of two operating properties, as described in Note 4 to our consolidated financial statements. This amount excludes intangible assets associated with acquisitions.

(2)Includes sales of our wholesale data center and ownership interests in data center shells through newly-formed unconsolidated real estate joint ventures, as described in Note 4 to our consolidated financial statements.

(3)Includes impairment recognized on six operating properties and a parcel of land, as described in Note 4 to our consolidated financial statements.