Annual report pursuant to Section 13 and 15(d)

Schedule III - Real Estate and Accumulated Depreciation

v3.22.4
Schedule III - Real Estate and Accumulated Depreciation
 12 Months Ended
Dec. 31, 2022
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 $ —  $ 26,715  $ 58,002  $ 45,315  $ 26,715  $ 103,317  $ 130,032  $ (30,601) 1973/2011 8/7/2015
100 Secured Gateway (O) Huntsville, AL —  —  71,159  34  —  71,193  71,193  (4,121) 2020 3/23/2010
1000 Redstone Gateway (O) Huntsville, AL 8,880  —  20,533  108  —  20,641  20,641  (5,045) 2013 3/23/2010
1100 Redstone Gateway (O) Huntsville, AL 9,547  —  19,593  100  —  19,693  19,693  (4,408) 2014 3/23/2010
114 National Business Parkway (O) Annapolis Junction, MD —  364  3,109  427  364  3,536  3,900  (1,779) 2002 6/30/2000
1200 Redstone Gateway (O) Huntsville, AL 11,012  —  22,389  121  —  22,510  22,510  (5,077) 2013 3/23/2010
1201 M Street SE (O) Washington, DC —  —  49,775  10,384  —  60,159  60,159  (23,155) 2001 9/28/2010
1201 Winterson Road (O) Linthicum, MD —  2,130  17,202  924  2,130  18,126  20,256  (6,403) 1985/2017 4/30/1998
1220 12th Street SE (O) Washington, DC —  —  42,464  9,919  —  52,383  52,383  (21,522) 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  6,392  1,906  14,015  15,921  (8,472) 1990 9/28/1998
132 National Business Parkway (O) Annapolis Junction, MD —  2,917  12,259  4,984  2,917  17,243  20,160  (11,464) 2000 5/28/1999
133 National Business Parkway (O) Annapolis Junction, MD —  2,517  10,068  6,733  2,517  16,801  19,318  (11,461) 1997 9/28/1998
134 National Business Parkway (O) Annapolis Junction, MD —  3,684  7,517  5,958  3,684  13,475  17,159  (8,950) 1999 11/13/1998
1340 Ashton Road (O) Hanover, MD —  905  3,620  2,631  905  6,251  7,156  (3,639) 1989 4/28/1999
13450 Sunrise Valley Drive (O) Herndon, VA —  1,386  5,576  4,955  1,386  10,531  11,917  (7,040) 1998 7/25/2003
13454 Sunrise Valley Drive (O) Herndon, VA —  2,847  11,986  10,345  2,847  22,331  25,178  (13,637) 1998 7/25/2003
135 National Business Parkway (O) Annapolis Junction, MD —  2,484  9,750  7,085  2,484  16,835  19,319  (11,512) 1998 12/30/1998
1362 Mellon Road (O) Hanover, MD —  950  3,864  1,953  950  5,817  6,767  (1,577) 2006 2/10/2006
13857 McLearen Road (O) Herndon, VA —  3,507  30,177  5,715  3,507  35,892  39,399  (14,907) 2007 7/11/2012
140 National Business Parkway (O) Annapolis Junction, MD —  3,407  24,167  1,811  3,407  25,978  29,385  (12,361) 2003 12/31/2003
141 National Business Parkway (O) Annapolis Junction, MD —  2,398  9,538  4,832  2,398  14,370  16,768  (10,153) 1990 9/28/1998
14280 Park Meadow Drive (O) Chantilly, VA —  3,731  15,953  5,621  3,731  21,574  25,305  (11,413) 1999 9/29/2004
1460 Dorsey Road (L) Hanover, MD —  1,577  183  —  1,577  183  1,760  —  (6) 2/28/2006
14840 Conference Center Drive (O) Chantilly, VA —  1,572  8,175  5,728  1,572  13,903  15,475  (8,420) 2000 7/25/2003
14850 Conference Center Drive (O) Chantilly, VA —  1,615  8,358  7,439  1,615  15,797  17,412  (8,032) 2000 7/25/2003
14900 Conference Center Drive (O) Chantilly, VA —  3,436  14,402  9,371  3,436  23,773  27,209  (14,901) 1999 7/25/2003
1501 South Clinton Street (O) Baltimore, MD —  27,964  51,990  44,816  27,964  96,806  124,770  (34,787) 2006 10/27/2009
15049 Conference Center Drive (O) Chantilly, VA —  4,415  20,365  17,846  4,415  38,211  42,626  (22,574) 1997 8/14/2002
15059 Conference Center Drive (O) Chantilly, VA —  5,753  13,615  6,313  5,753  19,928  25,681  (11,364) 2000 8/14/2002
1550 West Nursery Road (O) Linthicum, MD —  14,071  16,930  —  14,071  16,930  31,001  (7,047) 2009 10/28/2009
1560 West Nursery Road (O) Linthicum, MD —  1,441  113  —  1,441  113  1,554  (24) 2014 10/28/2009
1610 West Nursery Road (O) Linthicum, MD —  259  246  —  259  246  505  (36) 2016 4/30/1998
1616 West Nursery Road (O) Linthicum, MD —  393  3,323  75  393  3,398  3,791  (449) 2017 4/30/1998
1622 West Nursery Road (O) Linthicum, MD —  393  2,542  —  393  2,542  2,935  (372) 2016 4/30/1998
16442 Commerce Drive (O) Dahlgren, VA —  613  2,582  1,147  613  3,729  4,342  (2,134) 2002 12/21/2004
16480 Commerce Drive (O) Dahlgren, VA —  1,856  7,425  2,772  1,856  10,197  12,053  (5,203) 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  1,040  522  3,130  3,652  (1,689) 2002 12/21/2004
16539 Commerce Drive (O) Dahlgren, VA —  688  2,860  2,345  688  5,205  5,893  (3,190) 1990 12/21/2004
16541 Commerce Drive (O) Dahlgren, VA —  773  3,094  2,630  773  5,724  6,497  (3,261) 1996 12/21/2004
16543 Commerce Drive (O) Dahlgren, VA —  436  1,742  879  436  2,621  3,057  (1,467) 2002 12/21/2004
1751 Pinnacle Drive (O) McLean, VA —  10,486  42,339  34,512  10,486  76,851  87,337  (45,785) 1989/1995 9/23/2004
1753 Pinnacle Drive (O) McLean, VA —  8,275  34,353  25,142  8,275  59,495  67,770  (30,720) 1976/2004 9/23/2004
206 Research Boulevard (O) Aberdeen, MD —  —  —  —  —  —  —  —  2012 9/14/2007
209 Research Boulevard (O) Aberdeen, MD —  134  1,711  543  134  2,254  2,388  (772) 2010 9/14/2007
210 Research Boulevard (O) Aberdeen, MD —  113  1,402  536  113  1,938  2,051  (610) 2010 9/14/2007
2100 L Street (O) Washington, DC —  57,385  94,784  —  57,385  94,784  152,169  (4,385) 2020 8/11/2015
2100 Rideout Road (O) Huntsville, AL —  —  7,336  3,015  —  10,351  10,351  (2,760) 2016 3/23/2010
22289 Exploration Drive (O) Lexington Park, MD —  1,422  5,719  2,148  1,422  7,867  9,289  (4,585) 2000 3/24/2004
22299 Exploration Drive (O) Lexington Park, MD —  1,362  5,791  3,084  1,362  8,875  10,237  (5,531) 1998 3/24/2004
22300 Exploration Drive (O) Lexington Park, MD —  1,094  5,038  2,772  1,094  7,810  8,904  (4,640) 1997 11/9/2004
22309 Exploration Drive (O) Lexington Park, MD —  2,243  10,419  8,179  2,243  18,598  20,841  (9,668) 1984/1997 3/24/2004
23535 Cottonwood Parkway (O) California, MD —  692  3,051  648  692  3,699  4,391  (2,358) 1984 3/24/2004
250 W Pratt St (O) Baltimore, MD —  8,057  34,588  19,811  8,057  54,399  62,456  (22,224) 1985 3/19/2015
2600 Park Tower Drive (O) Vienna, VA —  20,284  34,443  5,977  20,284  40,420  60,704  (9,764) 1999 4/15/2015
2691 Technology Drive (O) Annapolis Junction, MD —  2,098  17,334  9,191  2,098  26,525  28,623  (13,031) 2005 5/26/2000
2701 Technology Drive (O) Annapolis Junction, MD —  1,737  15,266  7,118  1,737  22,384  24,121  (14,080) 2001 5/26/2000
2711 Technology Drive (O) Annapolis Junction, MD —  2,251  21,611  4,459  2,251  26,070  28,321  (16,361) 2002 11/13/2000
2720 Technology Drive (O) Annapolis Junction, MD —  3,863  29,272  3,219  3,863  32,491  36,354  (15,238) 2004 1/31/2002
2721 Technology Drive (O) Annapolis Junction, MD —  4,611  14,597  3,828  4,611  18,425  23,036  (11,406) 2000 10/21/1999
2730 Hercules Road (O) Annapolis Junction, MD —  8,737  31,612  9,540  8,737  41,152  49,889  (25,143) 1990 9/28/1998
30 Light Street (O) Baltimore, MD —  —  12,101  1,056  —  13,157  13,157  (2,742) 2009 8/7/2015
300 Secured Gateway (O) Annapolis Junction, MD —  —  25,384  —  —  25,384  25,384  —  (7) 3/23/2010
300 Sentinel Drive (O) Annapolis Junction, MD —  1,517  59,165  2,526  1,517  61,691  63,208  (20,225) 2009 11/14/2003
302 Sentinel Drive (O) Annapolis Junction, MD —  2,648  29,687  3,802  2,648  33,489  36,137  (12,102) 2007 11/14/2003
304 Sentinel Drive (O) Annapolis Junction, MD —  3,411  24,917  5,335  3,411  30,252  33,663  (13,355) 2005 11/14/2003
306 Sentinel Drive (O) Annapolis Junction, MD —  3,260  22,592  3,720  3,260  26,312  29,572  (11,085) 2006 11/14/2003
308 Sentinel Drive (O) Annapolis Junction, MD —  1,422  26,208  2,365  1,422  28,573  29,995  (8,761) 2010 11/14/2003
310 Sentinel Way (O) Annapolis Junction, MD —  2,372  43,312  —  2,372  43,312  45,684  (7,180) 2016 11/14/2003
310 The Bridge Street (O) Huntsville, AL —  261  26,530  5,958  261  32,488  32,749  (13,337) 2009 8/9/2011
312 Sentinel Way (O) Annapolis Junction, MD —  3,138  27,797  —  3,138  27,797  30,935  (5,779) 2014 11/14/2003
314 Sentinel Way (O) Annapolis Junction, MD —  1,254  7,741  —  1,254  7,741  8,995  (1,713) 2008 11/14/2003
316 Sentinel Way (O) Annapolis Junction, MD —  2,748  38,156  225  2,748  38,381  41,129  (10,394) 2011 11/14/2003
318 Sentinel Way (O) Annapolis Junction, MD —  2,185  28,426  562  2,185  28,988  31,173  (12,249) 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  (8,206) 2007 11/14/2003
322 Sentinel Way (O) Annapolis Junction, MD —  2,605  22,827  1,900  2,605  24,727  27,332  (10,090) 2006 11/14/2003
324 Sentinel Way (O) Annapolis Junction, MD —  1,656  23,018  42  1,656  23,060  24,716  (7,109) 2010 6/29/2006
4000 Market Street (O) Huntsville, AL 5,993  —  9,198  396  —  9,594  9,594  (858) 2018 3/23/2010
410 National Business Parkway (O) Annapolis Junction, MD —  1,831  23,257  2,259  1,831  25,516  27,347  (7,048) 2012 6/29/2006
4100 Market Street (O) Huntsville, AL 5,217  —  8,049  7  —  8,056  8,056  (710) 2019 3/23/2010
420 National Business Parkway (O) Annapolis Junction, MD —  2,370  29,550  208  2,370  29,758  32,128  (6,217) 2013 6/29/2006
430 National Business Parkway (O) Annapolis Junction, MD —  1,852  21,563  2,950  1,852  24,513  26,365  (6,632) 2011 6/29/2006
44408 Pecan Court (O) California, MD —  817  1,583  1,751  817  3,334  4,151  (2,259) 1986 3/24/2004
44414 Pecan Court (O) California, MD —  405  1,619  1,149  405  2,768  3,173  (1,861) 1986 3/24/2004
44417 Pecan Court (O) California, MD —  434  3,822  180  434  4,002  4,436  (2,385) 1989/2015 3/24/2004
44420 Pecan Court (O) California, MD —  344  890  311  344  1,201  1,545  (667) 1989 11/9/2004
44425 Pecan Court (O) California, MD —  1,309  3,506  2,395  1,309  5,901  7,210  (4,076) 1997 5/5/2004
45310 Abell House Lane (O) California, MD —  2,272  13,808  1,386  2,272  15,194  17,466  (4,357) 2011 8/30/2010
4600 River Road (O) College Park, MD —  —  24,573  —  —  24,573  24,573  (1,049) 2020 1/29/2008
46579 Expedition Drive (O) Lexington Park, MD —  1,406  5,796  2,987  1,406  8,783  10,189  (4,897) 2002 3/24/2004
46591 Expedition Drive (O) Lexington Park, MD —  1,200  7,199  4,394  1,200  11,593  12,793  (5,181) 2005 3/24/2004
4851 Stonecroft Boulevard (O) Chantilly, VA —  1,878  11,558  223  1,878  11,781  13,659  (5,307) 2004 8/14/2002
540 National Business Parkway (O) Annapolis Junction, MD —  2,035  31,840  41  2,035  31,881  33,916  (4,124) 2017 6/29/2006
550 National Business Parkway (O) Annapolis Junction, MD —  2,678  30,363  —  2,678  30,363  33,041  —  (7) 6/29/2006
5520 Research Park Drive (O) Catonsville, MD —  —  20,072  1,979  —  22,051  22,051  (7,741) 2009 4/4/2006
5522 Research Park Drive (O) Catonsville, MD —  —  4,550  855  —  5,405  5,405  (2,050) 2007 3/8/2006
560 National Business Parkway (O) Annapolis Junction, MD —  2,193  55,149  —  2,193  55,149  57,342  (233) 2022 6/29/2006
5801 University Research Court (O) College Park, MD 10,880  —  17,431  162  —  17,593  17,593  (2,294) 2018 1/29/2008
5825 University Research Court (O) College Park, MD 19,075  —  22,771  2,517  —  25,288  25,288  (8,978) 2008 1/29/2008
5850 University Research Court (O) College Park, MD 20,182  —  31,906  1,112  —  33,018  33,018  (10,623) 2008 1/29/2008
6000 Redstone Gateway (O) Huntsville, AL —  —  8,532  17  —  8,549  8,549  (415) 2020 3/23/2010
610 Guardian Way (O) Annapolis Junction, MD —  7,636  53,574  —  7,636  53,574  61,210  (1,572) 2021 6/29/2006
6200 Redstone Gateway (O) Huntsville, AL —  —  38,479  —  —  38,479  38,479  —  2022 3/23/2010
6700 Alexander Bell Drive (O) Columbia, MD —  1,755  7,019  10,504  1,755  17,523  19,278  (10,285) 1988 5/14/2001
6708 Alexander Bell Drive (O) Columbia, MD —  897  12,693  1,618  897  14,311  15,208  (5,238) 1988/2016 5/14/2001
6711 Columbia Gateway Drive (O) Columbia, MD —  2,683  23,239  2,885  2,683  26,124  28,807  (10,779) 2006-2007 9/28/2000
6716 Alexander Bell Drive (O) Columbia, MD —  1,242  4,969  5,323  1,242  10,292  11,534  (6,718) 1990 12/31/1998
6721 Columbia Gateway Drive (O) Columbia, MD —  1,753  34,090  9,263  1,753  43,353  45,106  (13,231) 2009 9/28/2000
6724 Alexander Bell Drive (O) Columbia, MD —  449  5,039  2,491  449  7,530  7,979  (4,349) 2001 5/14/2001
6731 Columbia Gateway Drive (O) Columbia, MD —  2,807  19,098  6,351  2,807  25,449  28,256  (14,983) 2002 3/29/2000
6740 Alexander Bell Drive (O) Columbia, MD —  1,424  4,209  7,131  1,424  11,340  12,764  (2,773) 1992 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)
6741 Columbia Gateway Drive (O) Columbia, MD —  675  1,711  176  675  1,887  2,562  (762) 2008 9/28/2000
6750 Alexander Bell Drive (O) Columbia, MD —  1,263  12,461  6,050  1,263  18,511  19,774  (11,751) 2001 12/31/1998
6760 Alexander Bell Drive (O) Columbia, MD —  890  3,561  3,915  890  7,476  8,366  (5,348) 1991 12/31/1998
6940 Columbia Gateway Drive (O) Columbia, MD —  3,545  9,916  12,340  3,545  22,256  25,801  (12,733) 1999 11/13/1998
6950 Columbia Gateway Drive (O) Columbia, MD —  3,596  28,307  3,223  3,596  31,530  35,126  (13,441) 1998/2019 10/22/1998
7000 Columbia Gateway Drive (O) Columbia, MD —  3,131  12,103  10,451  3,131  22,554  25,685  (11,944) 1999 5/31/2002
7000 Redstone Gateway (O) Huntsville, AL —  —  7,542  —  —  7,542  7,542  —  2022 (7) 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  (5,447) 1999 12/1/2005
7061 Columbia Gateway Drive (O) Columbia, MD —  729  3,094  2,909  729  6,003  6,732  (3,806) 2000 8/30/2001
7063 Columbia Gateway Drive (O) Columbia, MD —  902  3,684  3,470  902  7,154  8,056  (4,975) 2000 8/30/2001
7065 Columbia Gateway Drive (O) Columbia, MD —  919  3,763  3,174  919  6,937  7,856  (4,846) 2000 8/30/2001
7067 Columbia Gateway Drive (O) Columbia, MD —  1,829  11,823  8,125  1,829  19,948  21,777  (10,234) 2001 8/30/2001
7100 Redstone Gateway (O) Huntsville, AL —  —  12,983  —  —  12,983  12,983  (514) 2021 3/23/2010
7125 Columbia Gateway Drive (O) Columbia, MD —  20,487  49,925  27,278  20,487  77,203  97,690  (32,510) 1973/1999 6/29/2006
7130 Columbia Gateway Drive (O) Columbia, MD —  1,350  4,359  3,029  1,350  7,388  8,738  (4,363) 1989 9/19/2005
7134 Columbia Gateway Drive (O) Columbia, MD —  704  4,700  817  704  5,517  6,221  (2,144) 1990/2016 9/19/2005
7138 Columbia Gateway Drive (O) Columbia, MD —  1,104  3,518  2,963  1,104  6,481  7,585  (4,506) 1990 9/19/2005
7142 Columbia Gateway Drive (O) Columbia, MD —  1,342  7,148  2,851  1,342  9,999  11,341  (4,803) 1994/2018 9/19/2005
7150 Columbia Gateway Drive (O) Columbia, MD —  1,032  3,429  1,659  1,032  5,088  6,120  (2,165) 1991 9/19/2005
7150 Riverwood Drive (O) Columbia, MD —  1,821  4,388  3,436  1,821  7,824  9,645  (3,316) 2000 1/10/2007
7160 Riverwood Drive (O) Columbia, MD —  2,732  7,006  4,609  2,732  11,615  14,347  (5,835) 2000 1/10/2007
7170 Riverwood Drive (O) Columbia, MD —  1,283  3,096  2,387  1,283  5,483  6,766  (3,002) 2000 1/10/2007
7175 Riverwood Drive (O) Columbia, MD —  1,788  7,269  —  1,788  7,269  9,057  (1,661) 1996/2013 7/27/2005
7200 Redstone Gateway (O) Huntsville, AL —  —  8,348  81  —  8,429  8,429  (1,830) 2013 3/23/2010
7200 Riverwood Drive (O) Columbia, MD —  4,089  22,630  5,036  4,089  27,666  31,755  (14,245) 1986 10/13/1998
7205 Riverwood Drive (O) Columbia, MD —  1,367  21,419  —  1,367  21,419  22,786  (5,058) 2013 7/27/2005
7272 Park Circle Drive (O) Hanover, MD —  1,479  6,300  4,609  1,479  10,909  12,388  (6,471) 1991/1996 1/10/2007
7318 Parkway Drive (O) Hanover, MD —  972  3,888  2,284  972  6,172  7,144  (3,374) 1984 4/16/1999
7400 Redstone Gateway (O) Huntsville, AL —  —  9,223  75  —  9,298  9,298  (1,756) 2015 3/23/2010
7467 Ridge Road (O) Hanover, MD —  1,565  3,116  6,876  1,565  9,992  11,557  (5,137) 1990 4/28/1999
7500 Advanced Gateway (O) Huntsville, AL —  —  18,665  —  —  18,665  18,665  (1,201) 2020 3/23/2010
7600 Advanced Gateway (O) Huntsville, AL —  —  13,752  —  —  13,752  13,752  (826) 2020 3/23/2010
7740 Milestone Parkway (O) Hanover, MD 15,942  3,825  34,176  1,262  3,825  35,438  39,263  (11,179) 2009 7/2/2007
7770 Backlick Road (O) Springfield, VA —  6,387  78,892  1,669  6,387  80,561  86,948  (19,584) 2012 3/10/2010
7880 Milestone Parkway (O) Hanover, MD —  4,857  27,175  1,617  4,857  28,792  33,649  (5,068) 2015 9/17/2013
8000 Rideout Road (O) Huntsville, AL —  —  27,579  —  —  27,579  27,579  (529) 2021 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)
8100 Rideout Road (O) Huntsville, AL —  —  14,606  —  —  14,606  14,606  —  (7) 3/23/2010
8200 Rideout Road (O) Huntsville, AL —  —  43,115  —  —  43,115  43,115  —  2022 3/23/2010
8300 Rideout Road (O) Huntsville, AL —  —  47,658  —  —  47,658  47,658  —  2022 3/23/2010
8600 Advanced Gateway (O) Huntsville, AL —  —  27,312  —  —  27,312  27,312  (1,394) 2020 3/23/2010
8621 Robert Fulton Drive (O) Columbia, MD —  2,317  12,642  7,680  2,317  20,322  22,639  (9,467) 2005-2006 6/10/2005
8661 Robert Fulton Drive (O) Columbia, MD —  1,510  3,764  3,313  1,510  7,077  8,587  (4,129) 2002 12/30/2003
8671 Robert Fulton Drive (O) Columbia, MD —  1,718  4,280  4,848  1,718  9,128  10,846  (5,418) 2002 12/30/2003
870 Elkridge Landing Road (O) Linthicum, MD —  2,003  9,442  10,464  2,003  19,906  21,909  (13,432) 1981 8/3/2001
8800 Redstone Gateway (O) Huntsville, AL 11,565  —  18,470  —  —  18,470  18,470  (1,437) 2019 3/23/2010
891 Elkridge Landing Road (O) Linthicum, MD —  1,165  4,772  3,994  1,165  8,766  9,931  (5,750) 1984 7/2/2001
901 Elkridge Landing Road (O) Linthicum, MD —  1,156  4,437  7,069  1,156  11,506  12,662  (5,724) 1984 7/2/2001
911 Elkridge Landing Road (O) Linthicum, MD —  1,215  4,861  3,347  1,215  8,208  9,423  (5,448) 1985 4/30/1998
938 Elkridge Landing Road (O) Linthicum, MD —  922  4,748  1,516  922  6,264  7,186  (3,619) 1984 7/2/2001
939 Elkridge Landing Road (O) Linthicum, MD —  939  3,756  4,687  939  8,443  9,382  (6,313) 1983 4/30/1998
Arundel Preserve (L) Hanover, MD —  13,352  9,844  —  13,352  9,844  23,196  —  (6) 7/2/2007
Canton Crossing Land (L) Baltimore, MD —  17,285  8,438  1,076  17,285  9,514  26,799  (17) (6) 10/27/2009
Canton Crossing Util Distr Ctr (O) Baltimore, MD —  6,100  10,450  1,974  6,100  12,424  18,524  (7,510) 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  8,332  —  705  8,332  9,037  (113) 2022 (7) 3/24/2004
M Square Research Park (L) College Park, MD —  —  3,230  —  —  3,230  3,230  —  (6) 1/29/2008
MR Land (L) Northern Virginia —  9,038  809  —  9,038  809  9,847  —  (6) 11/8/2018
National Business Park North (L) Annapolis Junction, MD —  15,554  21,463  —  15,554  21,463  37,017  —  (6) 6/29/2006
North Gate Business Park (L) Aberdeen, MD —  1,755  5  —  1,755  5  1,760  —  (6) 9/14/2007
NoVA Office A (O) Chantilly, VA —  2,096  46,849  —  2,096  46,849  48,945  (9,266) 2015 7/18/2002
NoVA Office B (O) Chantilly, VA —  739  38,376  —  739  38,376  39,115  (5,695) 2016 7/18/2002
NoVA Office C (O) Chantilly, VA —  7,751  80,771  —  7,751  80,771  88,522  (2,472) 2021 7/18/2002
NoVA Office D (O) Chantilly, VA —  6,587  40,559  —  6,587  40,559  47,146  (5,483) 2017 7/2/2013
Oak Grove A (O) Northern Virginia —  12,866  41,488  —  12,866  41,488  54,354  (2,232) 2020 11/1/2018
Oak Grove B (O) Northern Virginia —  12,866  41,443  —  12,866  41,443  54,309  (2,866) 2019 11/1/2018
Oak Grove C (O) Northern Virginia —  11,741  77,526  —  11,741  77,526  89,267  (1,369) 2022 11/1/2018
Oak Grove D (O) Northern Virginia —  11,741  71,279  —  11,741  71,279  83,020  (260) 2022 11/1/2018
Old Annapolis Road (O) Columbia, MD —  1,637  5,500  6,902  1,637  12,402  14,039  (5,882) 1974/1985 12/14/2000
P2 A (O) (8) Northern Virginia —  16,853  40,159  —  16,853  40,159  57,012  (2,576) 2020 5/2/2019
P2 B (O) (8) Northern Virginia —  22,839  36,388  —  22,839  36,388  59,227  (1,953) 2020 5/2/2019
P2 C (O) (8) Northern Virginia —  14,869  31,597  —  14,869  31,597  46,466  (1,485) 2020 5/2/2019
Patriot Ridge (L) Springfield, VA —  18,517  14,599  —  18,517  14,599  33,116  —  (6) 3/10/2010
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)
Project EL (O) Confidential-USA —  7,190  46,746  —  7,190  46,746  53,936  (1,705) 2021 1/20/2006
Project EX (O) Confidential-USA —  13,010  19,107  —  13,010  19,107  32,117  (1,697) 2018 7/16/2008
PS A (O) Northern Virginia —  4,078  8,808  —  4,078  8,808  12,886  —  (7) 1/27/2005
PS B (O) Northern Virginia —  3,468  4,407  —  3,468  4,407  7,875  —  (7) 1/27/2005
Redstone Gateway (L) Huntsville, AL —  —  25,386  —  —  25,386  25,386  —  (6) 3/23/2010
Sentry Gateway - T (O) San Antonio, TX —  14,020  38,804  13  14,020  38,817  52,837  (15,413) 1982/2008 3/30/2005
Sentry Gateway - V (O) San Antonio, TX —  —  1,066  —  —  1,066  1,066  (374) 2007 3/30/2005
Sentry Gateway - W (O) San Antonio, TX —  —  1,884  71  —  1,955  1,955  (651) 2009 3/30/2005
Sentry Gateway - X (O) San Antonio, TX —  1,964  21,178  —  1,964  21,178  23,142  (6,434) 2010 1/20/2006
Sentry Gateway - Y (O) San Antonio, TX —  1,964  21,298  —  1,964  21,298  23,262  (6,472) 2010 1/20/2006
Sentry Gateway - Z (O) San Antonio, TX —  1,964  30,573  —  1,964  30,573  32,537  (5,968) 2015 6/14/2005
SP Manassas (L) Manassas, VA —  8,156  921  —  8,156  921  9,077  —  (6) 7/24/2019
Westfields - Park Center (L) Chantilly, VA —  8,667  3,170  —  8,667  3,170  11,837  —  (6) 7/2/2013
Other Developments, including
   intercompany eliminations (V)		 Various —  —  1,169  258  —  1,427  1,427  (135) Various Various
$ 118,293  $ 709,752  $ 3,606,680  $ 670,105  $ 709,752  $ 4,276,785  $ 4,986,537  $ (1,273,448)
(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 $211.0 million, term loan facilities of $123.9 million, unsecured senior notes of $1.8 billion, unsecured notes payable of $597,000, and deferred financing costs, net of premiums, on the remaining loans of $541,000.
(3)The aggregate cost of these assets for federal income tax purposes was approximately $3.7 billion as of December 31, 2022.
(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, 2022.
(7)Under development as of December 31, 2022.
(8)Classified as held for sale as of December 31, 2022.
The following table summarizes our changes in cost of properties for the years ended December 31, 2022, 2021 and 2020 (in thousands):
2022 2021 2020
Beginning balance $ 4,959,709  $ 4,686,802  $ 4,348,006 
Improvements and other additions 350,702  342,684  405,940 
Sales (1) (323,874) (103,097) (65,475)
Impairments —  —  (1,530)
Other dispositions —  (4,511) (139)
Reclassification from right-of-use asset —  37,831  — 
Ending balance $ 4,986,537  $ 4,959,709  $ 4,686,802 
The following table summarizes our changes in accumulated depreciation for the same time periods (in thousands):
2022 2021 2020
Beginning balance $ 1,234,908  $ 1,124,253  $ 1,007,120 
Depreciation expense 124,803  130,604  119,377 
Sales (1) (86,263) (15,438) (2,105)
Other dispositions —  (4,511) (139)
Ending balance $ 1,273,448  $ 1,234,908  $ 1,124,253 
(1)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.