Common use of Partner Clause in Contracts

Partner. By: -------------------------------- Name: -------------------------------- Its: -------------------------------- Exhibit C-1 Under penalties of perjury, I declare that I have examined this certification and, to the best of my knowledge and belief, it is true, correct, and complete, and I further declare that I have authority to sign this document on behalf of Partner. Date: ----------------- --------------------------------------- Name: Title: Exhibit C-2 For Redeeming Limited Partners that are individuals: CERTIFICATION OF NON-FOREIGN STATUS Under section 1445(e) of the Internal Revenue Code of 1986, as amended (the "Code"), in the event of a disposition by a non-U.S. person of a partnership interest in a partnership in which (i) 50% or more of the value of the gross assets consists of United States real property interests ("USRPIs"), as defined in section 897(c) of the Code, and (ii) 90% or more of the value of the gross assets consists of USRPIs, cash, and cash equivalents, the transferee will be required to withhold 10% of the amount realized by the non-U.S. person upon the disposition. To inform Columbia Equity Trust, Inc. (the "Company") and Columbia Equity, LP (the "Partnership") that no withholding is required with respect to my redemption of my units of limited partnership interest in the Partnership, I, ___________, hereby certify the following:

Partner. (entity name) By: -------------------------------- ------------------------------------- Name: -------------------------------- Its----------------------------------- Title: -------------------------------- Exhibit C-1 ---------------------------------- Under penalties of perjury, I declare that I have examined this certification and, to the best of my knowledge and belief, it is true, correct, and complete, and I further declare that I have authority to sign this document on behalf of Partner. Date: ----------------- --------------------------------------- Name: -------------------------- --------------------------------- Title: Exhibit C-2 --------------------------------- For Redeeming Limited Exchanging Partners that are individuals: CERTIFICATION OF NON-FOREIGN STATUS Under section Section 1445(e) of the Internal Revenue Code of 1986, as amended (the "Code"), in the event of a disposition by a non-U.S. person of a partnership interest in a partnership in which (i) 50% or more of the value of the gross assets consists of United States real property interests ("USRPIs"), as defined in section 897(c) of the Code, and (ii) 90% or more of the value of the gross assets consists of USRPIs, cash, and cash equivalents, the transferee will be required to withhold 10% of the amount realized by the non-U.S. person upon the disposition. To inform Columbia Equity Trust, Inc. Gladstone Commercial Corporation (the "CompanyGeneral Partner") and Columbia Equity, LP Gladstone Commercial Limited Partnership (the "Partnership") that no withholding is required with respect to my redemption of my units of limited partnership interest in the Partnership, I, _______________, hereby certify the following:

Partner. By: -------------------------------- ---------------------------------- Name: -------------------------------- Its: -------------------------------- Exhibit C-1 --------------------------------- Under penalties of perjury, I declare that I have examined this certification and, to the best of my knowledge and belief, it is true, correct, and complete, and I further declare that I have authority to sign this document on behalf of Partner. Date: ----------------- --------------------------------------- Name: Title: Exhibit C-2 :_______________ [NAME] _________________________________ Title For Redeeming Limited Partners that are individuals: CERTIFICATION OF NON-FOREIGN STATUS Under section 1445(e) of the Internal Revenue Code of 1986, as amended (the "Code"), in the event of a disposition by a non-U.S. person of a partnership interest in a partnership in which (i) 50% or more of the value of the gross assets consists of United States real property interests ("USRPIs"), as defined in section 897(c) of the Code, and (ii) 90% or more of the value of the gross assets consists of USRPIs, cash, and cash equivalents, the transferee will be required to withhold 10% of the amount realized by the non-U.S. person upon the disposition. To inform Columbia Equity TrustFirst States Group, Inc. (the "Company") and Columbia Equity, LP L.P. (the "Partnership") that no withholding is required with respect to my redemption of my units of limited partnership interest in the Partnership, I, ___________, hereby certify the following:

Partner. By: -------------------------------- -------------------------------------- Name: -------------------------------- ------------------------------------ Its: -------------------------------- Exhibit C-1 ------------------------------------- Under penalties of perjury, I declare that I have examined this certification and, to the best of my knowledge and belief, it is true, correct, and complete, and I further declare that I have authority to sign this document on behalf of Partner. Date: ----------------- --------------------------------------- Name: Title: [NAME] ----------------------------- ----------------------------------- Title Exhibit C-2 C-1 For Redeeming Limited Partners that are individuals: CERTIFICATION OF NON-FOREIGN STATUS Under section 1445(e) of the Internal Revenue Code of 1986, as amended (the "Code"), in the event of a disposition by a non-U.S. person of a partnership interest in a partnership in which (i) 50% or more of the value of the gross assets consists of United States real property interests ("USRPIs"), as defined in section 897(c) of the Code, and (ii) 90% or more of the value of the gross assets consists of USRPIs, cash, and cash equivalents, the transferee will be required to withhold 10% of the amount realized by the non-U.S. person upon the disposition. To inform Columbia Equity Medical Properties Trust, Inc. (the "Company") and Columbia EquityMPT Operating Partnership, LP L.P. (the "Partnership") that no withholding is required with respect to my redemption of my units of limited partnership interest in the Partnership, I, ___________, hereby certify the following:

Partner. By: -------------------------------- Name: -------------------------------- ------------------------------- Its: -------------------------------- Exhibit C-1 ------------------------------- Under penalties of perjury, I declare that I have examined this certification and, to the best of my knowledge and belief, it is true, correct, and complete, and I further declare that I have authority to sign this document on behalf of Partner. Date: [NAME] ----------------- --------------------------------------- Name: Title: Exhibit C-2 -------------------------------------------------------------------------------- Title For Redeeming Limited Partners that are individuals: CERTIFICATION OF NON-FOREIGN STATUS ----------------------------------- Under section 1445(e) of the Internal Revenue Code of 1986, as amended (the "Code"), in the event of a disposition by a non-U.S. person of a partnership interest in a partnership in which (i) 50% or more of the value of the gross assets consists of United States real property interests ("USRPIs"), as defined in section 897(c) of the Code, and (ii) 90% or more of the value of the gross assets consists of USRPIs, cash, and cash equivalents, the transferee will be required to withhold 10% of the amount realized by the non-U.S. person upon the disposition. To inform Columbia Equity Trust, Inc. (the "Company") and Columbia Equity, LP First Potomac Realty Investment Limited Partnership (the "Partnership") that no withholding is required with respect to my redemption of my units of limited partnership interest in the Partnership, I, ___________, hereby certify the following:

Partner. By: -------------------------------- -------------------------------------- Name: -------------------------------- ------------------------------------ Its: -------------------------------- Exhibit C-1 ------------------------------------- Under penalties of perjury, I declare that I have examined this certification and, to the best of my knowledge and belief, it is true, correct, and complete, and I further declare that I have authority to sign this document on behalf of Partner. Date: ----------------- --------------------------------------- Name: Title: [NAME] --------------------- ---------------------------- Title Exhibit C-2 C-1 For Redeeming Limited Partners that are individuals: CERTIFICATION OF NON-FOREIGN STATUS Under section 1445(e) of the Internal Revenue Code of 1986, as amended (the "Code"), in the event of a disposition by a non-U.S. person of a partnership interest in a partnership in which (i) 50% or more of the value of the gross assets consists of United States real property interests ("USRPIs"), as defined in section 897(c) of the Code, and (ii) 90% or more of the value of the gross assets consists of USRPIs, cash, and cash equivalents, the transferee will be required to withhold 10% of the amount realized by the non-U.S. person upon the disposition. To inform Columbia Equity Trust, Inc. Windrose Medical Properties Trust (the "Company") and Columbia EquityWindrose Medical Properties, LP L.P. (the "Partnership") that no withholding is required with respect to my redemption of my units of limited partnership interest in the Partnership, I, ___________, hereby certify the following: