THIRD MODIFICATION AGREEMENT Secured Loan

A.

Pursuant to the terms of a Loan Agreement between Borrower and Lender dated October 10, 2005 (as amended, the “Loan Agreement”), as amended by the Modification Agreement, dated September 14, 2006, and the Second Modification Agreement, dated September 29, 2006, Lender made a loan to Borrower in the principal amount of Nineteen Million Five Hundred Thousand Dollars ($19,500,000) (the “Loan”). The Loan is evidenced by a Promissory Note Secured by Deed of Trust dated as of the date of the Loan Agreement, executed by Borrower in favor of Lender, in the principal amount of the Loan (the “Note”), and is further evidenced by the documents described in the Loan Agreement as “Loan Documents”. The Note is secured by, among other things, a Deed of Trust With Absolute Assignment of Leases and Rents, Security Agreement and Fixture Filing (as amended, the “Deed of Trust”) dated October 10, 2005, executed by Borrower, as Trustor, to American Securities Company, as Trustee, in favor of Lender, as Beneficiary. The Deed of Trust was recorded October 12, 2005, as Instrument or Document No. 05-2452852, in the Official Records of Los Angeles County, California, and amended by the Memorandum of Modification Agreement Amending Deed of Trust, dated September 14, 2006, and recorded September 20, 2006, as Instrument or Document No. 06-2089145, in the Official Records of Los Angeles County, California, and the Memorandum of Second Modification Agreement Amending Deed of Trust, dated September 29, 2006 and recorded October 3, 2006, as Instrument or Document No. 06-2202262, in the Official Records of Los Angeles County, California.

B.

As of the date hereof, the outstanding principal balance of the Loan is $17,000,000 and the undisbursed commitment amount is $0.

C.

The Note, Deed of Trust, Loan Agreement, this Agreement, the other documents described in the Loan Agreement as “Loan Documents”, together with all modifications and amendments thereto and any document required hereunder, are collectively referred to herein as the “Loan Documents”.

D.

By this Agreement, Borrower and Lender intend to modify and amend certain terms and provisions of the Loan Documents.

1.

CONDITIONS PRECEDENT . The following are conditions precedent to Lender’s obligations under this Agreement:

1.1

Receipt and approval by Lender of a date down to Title Policy No. 201057070 dated October 12, 2005, issued by Chicago Title Insurance Company (“Title Company”) and assurance acceptable to Lender, including, without limitation, CLTA Endorsement No. 110.5, without deletion or exception other than those expressly approved by Lender in writing, that the priority and validity of the Deed of Trust has not been and will not be impaired by this Agreement or the transactions contemplated hereby;

1.2

Receipt by Lender of the executed originals of this Agreement, the Amended and Restated Promissory Note Secured by Deed of Trust, which note amends, restates and replaces the Note (the “Amended Note”), the Amended and Restated Repayment Guaranty, which guaranty amends, restates and replaces the repayment guaranties previously executed by Thomas Properties Group, Inc., and Thomas Properties Group, L.P. (the “Amended Guaranty”), the short form of this Agreement (the “Short Form”) and any and all other documents and agreements which are required by this Agreement or by any other Loan Document, each in form and content acceptable to Lender;

1.3

Recordation in the Official Records of the County where the Property is located of (i) the Short Form, and (ii) any other documents which are required to be recorded by this Agreement or by any other Loan Document (if any);

1.4

Reimbursement to Lender by Borrower of Lender’s costs and expenses incurred in connection with this Agreement and the transactions contemplated hereby, including, without limitation, title insurance costs, recording fees, attorneys’ fees, appraisal, engineers’ and inspection fees and documentation costs and charges, whether such services are furnished by Lender’s employees or agents or by independent contractors, an Internal Administrative Expense Fee in the amount of $2,500, and an Appraisal Fee in the amount of $8,400;

1.5

The representations and warranties contained in this Agreement are true and correct;

1.6

All payments due and owing to Lender under the Loan Documents have been paid current as of the effective date of this Agreement; and

1.7

The payment to Lender of an extension fee in the amount of $170,000.

2.

INCORPORATION OF RECITALS; EFFECTIVE DATE . The foregoing recitals are incorporated herein as an agreement of Borrower and Lender. The date of this Agreement is for reference purposes only. With the exception of the Borrower’s and Lender’s obligations under the Amended Note, the effective date of Borrower’s and Lender’s obligations under this Agreement is the date of recordation of the Short Form in the Official Records of Los Angeles County, California (the “Effective Date”). The effective date of Borrower’s and Lender’s obligations under the Amended Note shall be October 10, 2009.

3.

REPRESENTATIONS AND WARRANTIES . Borrower hereby represents and warrants that no Default, breach or failure of condition has occurred, or would exist with notice or the lapse of time or both, under any of the Loan Documents (as modified by this Agreement) and that all representations and warranties herein and in the other Loan Documents are true and correct, which representations and warranties shall survive execution of this Agreement.

4.

MODIFICATION OF LOAN DOCUMENTS . The Loan Documents are hereby supplemented and modified to incorporate the following, which shall supersede and prevail over any conflicting provisions of the Loan Documents:

4.1

Defined Terms . Section 1.1 of the Loan Agreement is hereby amended as follows:

(a)

First Extended Maturity Date . The defined term “First Extended Maturity Date” is hereby deleted and replaced in its entirety with the following:

(b)

Loan . The defined term “Loan” is hereby deleted and replaced in its entirety with the following:

(c)

“ Original Maturity Date ” The defined term “Original Maturity Date” is hereby deleted and replaced in its entirety with the following:

(d)

Par FAR Value . A new defined term “Par FAR Value” is hereby added as follows:

(e)

Par Land Value . A new defined term “Par Land Value” is hereby added as follows:

(f)

Par Loan Amount . A new defined term “Par Loan Amount” is hereby added as follows:

(g)

“ Prime Rate ”. The defined term “Prime Rate” is hereby deleted.

(h)

Release Price . A new defined term “Release Price” is hereby added as follows:

(i)

“ Second Extended Maturity Date ” The defined term “Second Extended Maturity Date” is hereby deleted and replaced in its entirety with the following:

(j)

“ Third Extended Maturity Date ” The defined term “Third Extended Maturity Date” is hereby deleted and replaced in its entirety with the following:

(k)

“ Variable Rate ”. The defined term “Variable Rate” is hereby deleted.

4.2

Partial Reconveyance of Lots . Sections 2.9(d)(ii) and 2.9(d)(iii) of the Loan Agreement are hereby deleted in their entirety.

4.3

First Option to Extend . Section 2.10 of the Loan Agreement is hereby deleted and replaced in its entirety with the following:

(a)

Borrower shall provide Lender with written notice of Borrower’s request to exercise the First Option to Extend not more than ninety (90) days but not less than thirty (30) days prior to the Original Maturity Date; and

(b)

As of the date of Borrower’s delivery of notice of request to exercise the First Option to Extend, and as of the Original Maturity Date, no Default shall have occurred and be continuing, and no event or condition which, with the giving of notice or the passage of time or both, would constitute a Default shall have occurred and be continuing, and Borrower shall so certify in writing; and

(c)

Borrower shall execute or cause the execution of all documents reasonably required by Lender to exercise the First Option to Extend and shall deliver to Lender, at Borrower’s sole cost and expense, such title insurance endorsements reasonably required by Lender; and

(d)

Guarantor shall have confirmed that it remains in compliance with the financial covenants in the Guaranty; and

(e)

On the Original Maturity Date, Borrower shall pay to Lender an extension fee in the amount of three eighths of one percent (.375%) of the total commitment amount of the Loan, as determined on the Original Maturity Date; and

(f)

At Lender’s option, Lender shall have received a written appraisal dated within 90 days of the Original Maturity Date and prepared in conformance with the requirements of the Comptroller of the Currency confirming to the satisfaction of Lender that the commitment amount of the Loan as a percentage of the as-is bulk value of the portion of the Property then remaining encumbered by the Deed of Trust (after adjustment for senior liens and regular and special tax assessments) as of the Original Maturity Date does not exceed the Loan-to-Value Percentage; provided, however, if such as-is bulk value is not adequate to meet the required Loan-to-Value Percentage, then Borrower shall pay down the outstanding principal balance of the Loan such that said Loan-to-Value Percentage may be met. Any amounts repaid may not be reborrowed; and

(g)

Borrower shall repay $2,500,000 of the outstanding principal amount of the Loan; provided, that (i) any amount repaid in accordance with clause (f) above and/or (ii) any Release Price paid pursuant to Section 2.9, shall be credited against such $2,500,000 payment. By way of example, if Borrower repays $1,000,000 in accordance with clause (f) above and pays $1,000,000 in Release Prices pursuant to Section 2.9, then Borrower shall be required to repay an additional $500,000 in accordance with this clause (g). Notwithstanding the foregoing, if the outstanding principal amount of the Loan is less than $14,500,000 as of the Original Maturity Date, then Borrower shall not be required to make any payments in accordance with this clause (g). Any amounts repaid may not be reborrowed.

4.4

Second Option to Extend . Section 2.11 of the Loan Agreement is hereby deleted and replaced in its entirety with the following:

(a)

Borrower shall provide Lender with written notice of Borrower’s request to exercise the Second Option to Extend not more than ninety (90) days but not less than thirty (30) days prior to the First Extended Maturity Date; and

(b)

As of the date of Borrower’s delivery of notice of request to exercise the Second Option to Extend, and as of the First Extended Maturity Date, no Default shall have occurred and be continuing, and no event or condition which, with the giving of notice or the passage of time or both, would constitute a Default shall have occurred and be continuing, and Borrower shall so certify in writing; and

(c)

Borrower shall execute or cause the execution of all documents reasonably required by Lender to exercise the Second Option to Extend and shall deliver to Lender, at Borrower’s sole cost and expense, such title insurance endorsements reasonably required by Lender; and

(d)

Guarantor shall have confirmed that it remains in compliance with the financial covenants in the Guaranty; and

(e)

On the First Extended Maturity Date, Borrower shall pay to Lender an extension fee in the amount of three eighths of one percent (.375%) of the total commitment amount of the Loan, as determined on the First Extended Maturity Date; and

(f)

At Lender’s option, Lender shall have received a written appraisal dated within 90 days of the First Extended Maturity Date and prepared in conformance with the requirements of the Comptroller of the Currency confirming to the satisfaction of Lender that the commitment amount of the Loan as a percentage of the as-is bulk value of the portion of the Property then remaining encumbered by the Deed of Trust (after adjustment for senior liens and regular and special tax assessments) as of the First Extended Maturity Date does not exceed the Loan-to-Value Percentage; provided, however, if such as-is bulk value is not adequate to meet the required Loan-to-Value Percentage, then Borrower shall pay down the outstanding principal balance of the Loan such that said Loan-to-Value Percentage may be met. Any amounts repaid may not be reborrowed; and

(g)

Borrower shall repay $2,500,000 of the outstanding principal amount of the Loan; provided, that (i) any amount repaid in accordance with clause (f) above and/or (ii) any Release Price paid pursuant to Section 2.9 between the Original Maturity Date and the First Extended Maturity Date, shall be credited against such $2,500,000 payment. By way of example, if Borrower repays $1,000,000 in accordance with clause (f) above and pays $1,000,000 in Release Prices pursuant to Section 2.9 between the Original Maturity Date and the First Extended Maturity Date, then Borrower shall be required to repay an additional $500,000 in accordance with this clause (g). Notwithstanding the foregoing, if the outstanding principal amount of the Loan is less than $12,000,000 as of the Original Maturity Date, then Borrower shall not be required to make any payments in accordance with this clause (g). Any amounts repaid may not be reborrowed.

4.5

Third Option to Extend . Section 2.12 of the Loan Agreement is hereby deleted and replaced in its entirety with the following:

(a)

Borrower shall provide Lender with written notice of Borrower’s request to exercise the Third Option to Extend not more than ninety (90) days but not less than thirty (30) days prior to the Second Extended Maturity Date; and

(b)

As of the date of Borrower’s delivery of notice of request to exercise the Third Option to Extend, and as of the Second Extended Maturity Date, no Default shall have occurred and be continuing, and no event or condition which, with the giving of notice or the passage of time or both, would constitute a Default shall have occurred and be continuing, and Borrower shall so certify in writing; and

(c)

Borrower shall execute or cause the execution of all documents reasonably required by Lender to exercise the Third Option to Extend and shall deliver to Lender, at Borrower’s sole cost and expense, such title insurance endorsements reasonably required by Lender; and

(d)

Guarantor shall have confirmed that it remains in compliance with the financial covenants in the Guaranty; and

(e)

On the Second Extended Maturity Date, Borrower shall pay to Lender an extension fee in the amount of three eighths of one percent (.375%) of the total commitment amount of the Loan, as determi