Exhibit 21
List of Subsidiaries
The following sets forth the subsidiaries of the Registrant and their respective states of incorporation or organization:
| Name | State | |
| American Office Park Properties, TPGP, Inc. | California | |
| PSBP QRS, Inc. | California | |
| Hernmore, Inc. | Maryland | |
| AOPP Acquisition Corp. Two | California | |
| Tenant Advantage, Inc. | California | |
| PS Business Parks, L.P. | California | |
| PSBP Northpointe D, L.L.C. | Virginia | |
| PSBP Monroe, L.L.C. | Virginia | |
| Monroe Parkway, L.L.C. | Virginia | |
| Metro Park I, L.L.C. | Delaware | |
| Metro Park II, L.L.C. | Delaware | |
| Metro Park III, L.L.C. | Delaware | |
| Metro Park IV, L.L.C. | Delaware | |
| Metro Park V, L.L.C. | Delaware | |
| Metro Park Gude, L.L.C. | Delaware | |
| PSBP Westwood GP, L.L.C. | Delaware | |
| PSBP Westwood, L.P. | Delaware | |
| PSBP Industrial, L.L.C. | Delaware | |
| Miami International Commerce Center | Florida | |
| REVX-098, L.L.C. | Delaware | |
| PS Rose Canyon, L.L.C. | Delaware | |
| PSBP Meadows L.L.C. | Delaware | |
| PSB Boca Commerce Park, L.L.C. | Florida | |
| PSB Wellington Commerce Park I, L.L.C. | Florida | |
| PSB Wellington Commerce Park II, L.L.C. | Florida | |
| PSB Wellington Commerce Park III, L.L.C. | Florida |