Supplemental Operating and Financial Data Third Quarter 2015 1001 17thStreet, Denver, CO 1300 www.franklinstreetproperties.com Franklin Street Properties Corp. 401 Edgewater Place Wakefield, MA 01880 (781)557-1300

Table of Contents Page Page Company Overview 3 Tenant Analysis and Leasing Activity Tenants by Industry 18 Key Financial Data 20 Largest Tenants with Annualized Rent and Remaining Term 19 Financial Highlights 4 Leasing Activity 20 Income Statements 5 Lease Expirations by Square Feet 21 Balance Sheets 6 Lease Expirations with Annualized Rent per Square Foot 22 Cash Flow Statements 7 Capital Expenditures 23 Property Net Operating Income (NOI) 8 Transaction Activity 24 Reconciliation FFO & AFFO 9 Loan Portfolio of Secured Real Estate 25 EBITDA 10 Property NOI 11 Net Asset Value Components 26 Debt Summary 12 Appendix: Definitions of Non-GAAP Measures FFO 27 Capital Analysis 13 EBITDA and NOI 28 AFFO 29 Owned and Managed Portfolio Overview 14-17 All financial information contained in this supplemental information package is unaudited. In addition, certain statements contained in this supplemental information package may be deemed to be forward-looking statements within the meaning of the federal securities laws. Although FSP believes that the expectations reflected in such forward-looking statements are based upon reasonable assumptions, it can give no assurance that its expectations will be achieved. Factors that could cause actual results to differ materially from) 63 V current expectations include general economic conditions, uncertainties relating to fiscal policy, changes in government regulations, regulatory uncertainty, geopolitical events, local real estate conditions, the performance of properties that FSP has acquired or may acquire, the timely lease-up of properties and other risks, detailed from time to time in) s63 V SEC reports. FSP assumes no obligation to update or supplement forward-looking statements that become untrue because of subsequent events. 1001 17thStreet, Denver, CO September 30, 2015 2

Company Overview Overview Snapshot (as of September 30, 2015) Franklin Street Properties Corp. ³)63 (NYSE MKT: FSP) is investing in Corporate Headquarters Wakefield, MA institutional-quality office properties in the U.S.)63 V strategy is to invest in select urban infill and central Fiscal Year-End 31-Dec business district (CBD) properties, with primary emphasis on our top five markets of Atlanta, Dallas, Denver, Total Properties 36 Houston, and Minneapolis. FSP seeks value-oriented investments with an eye towards long-term growth and Total Square Feet 9.6 Million appreciation, as well as current income. FSP is a Maryland corporation that operates in a manner intended to Trading Symbol FSP qualify as a real estate investment trust (REIT) for federal income tax purposes. )63 V real estate operations Exchange NYSE MKT include property acquisitions and dispositions, short-term financing, leasing, development and asset Common Shares Outstanding 100,187,405 management. Quarterly Dividend $0.19 Dividend Yield 7.1% Our Business Total Market Capitalization $2.0 Billion As of September 30, 2015, the Company owned and operated a portfolio of real estate consisting of 36 Insider Holdings 5.1% properties, managed 9 Sponsored REITs and held five promissory notes secured by mortgages on real estate owned by Sponsored REITs. From time-to-time, the Company may acquire real estate, make additional secured loans or acquire one of its Sponsored REITs. The Company may also pursue, on a selective basis, the sale of its properties in order to take advantage of the value creation and demand for its properties, or for geographic or property specific reasons. Management Team George J. Carter Scott H. Carter President, Chief Executive Officer Executive Vice President, General Chairman of the Board Counsel and Secretary John G. Demeritt Jeffrey B. Carter Executive Vice President, Chief Executive Vice President and Financial Officer & Treasurer Chief Investment Officer Janet Notopoulos Eriel Anchondo Executive Vice President and Director Senior Vice President of Operations Inquiries Inquires should be directed to: Georgia Touma 877-686-9496 or InvestorRelations@franklinstreetproperties.com 999 Peachtree Street, Atlanta GA September 30, 2015 3

Summary of Financial Highlights (in thousands except per share amounts, SF & number of properties) 30-Sep-15 30-Jun-15 31-Mar-15 31-Dec-14 30-Sep-14 Income Items: Rental revenue $ 60,386 $ 58,801 $ 59,013 $ 61,022 $ 59,728 Total revenue 61,877 60,233 60,507 62,489 61,190 Adjusted EBITDA* 32,567 32,642 31,097 33,182 33,973 Equity in losses of non-consolidated REITs (284) (38) (322) (269) (455) Net income 3,166 3,903 12,533 4,295 1,567 FFO* 26,954 27,188 25,672 27,525 27,904 Per Share Data: EPS $ 0.03 $ 0.04 $ 0.13 $ 0.04 $ 0.02 FFO* $ 0.27 $ 0.27 $ 0.26 $ 0.27 $ 0.28 Weighted Average Shares (diluted) 100,187 100,187 100,187 100,187 100,187 Closing share price $ 10.75 $ 11.31 $ 12.82 $ 12.27 $ 11.22 Dividend $ 0.19 $ 0.19 $ 0.19 $ 0.19 $ 0.19 Payout Ratio: 71% 70% 74% 69% 68% Balance Sheet Items: Real estate, net $ 1,530,691 $ 1,539,343 $ 1,486,897 $ 1,524,307 $ 1,542,012 Other assets, net 395,689 400,758 402,515 412,083 425,305 Total assets, net 1,926,380 1,940,101 1,889,412 1,936,390 1,967,317 Total liabilities, net 992,086 984,555 921,082 956,743 968,948 Shareholders' equity 934,294 955,546 968,330 979,647 998,369 Market Capitalization and Debt: Total Market Capitalization (a) $ 1,997,015 $ 2,053,120 $ 2,144,403 $ 2,117,299 $ 2,029,103 Total debt outstanding 920,000 920,000 860,000 888,000 905,000 Debt to Total Market Capitalization 46.1% 44.8% 40.1% 41.9% 44.6% Debt to Adjusted EBITDA 7.1 7.0 6.9 6.7 6.7 Owned Portfolio Leasing Statistics: Owned portfolio assets 36 36 36 38 39 Portfolio total SF 9,640,904 9,639,740 9,310,131 9,580,057 9,690,361 Portfolio % leased 90.5% 90.6% 90.4% 92.8% 93.3% (a) Total Market Capitalization is the closing share price multilplied by the number of shares outstanding plus total debt outstanding on that date. * See pages 9 & 10 for reconciliations of Net Income to FFO and Adjusted EBITDA, respectively, and the Appendix for Defintions of these Non-GAAP Measures beginning on page 27. September 30, 2015 4

Condensed Consolidated Income Statements ($ in thousands, except per share amounts) For the Nine For the For the Three Months Ended Months Ended For the Three Months Ended Year Ended 31-Mar-15 30-Jun-15 30-Sep-15 30-Sep-15 31-Mar-14 30-Jun-14 30-Sep-14 31-Dec-14 31-Dec-14 Revenue: Rental $ 59,013 $ 58,801 $ 60,386 $ 178,200 $ 61,597 $ 60,994 $ 59,728 $ 61,022 $ 243,341 Related party revenue: Management fees and interest income from loans 1,473 1,412 1,470 4,355 1,643 1,671 1,462 1,465 6,241 Other 21 20 21 62 23 76 - 2 101 Total revenue 60,507 60,233 61,877 182,617 63,263 62,741 61,190 62,489 249,683 Expenses: Real estate operating expenses 15,356 14,644 15,951 45,951 15,071 14,995 15,632 16,334 62,032 Real estate taxes and insurance 10,048 9,469 9,941 29,458 9,251 9,763 8,555 9,288 36,857 Depreciation and amortization 22,672 23,207 22,911 68,790 24,300 23,563 24,878 23,174 95,915 Selling, general and administrative 3,691 3,401 3,071 10,163 3,272 3,148 3,071 3,492 12,983 Interest 6,187 6,365 6,425 18,977 7,176 6,891 6,883 6,483 27,433 Total expenses 57,954 57,086 58,299 173,339 59,070 58,360 59,019 58,771 235,220 Income before interest income, equity in losses of non-consolidated REITs and taxes 2,553 3,147 3,578 9,278 4,193 4,381 2,171 3,718 14,463 Interest income 1 - - 1 1 1 - 1 3 Equity in losses of non-consolidated REITs (322) (38) (284) (644) (484) (552) (455) (269) (1,760) Gain on sale of properties, less applicable income tax 10,462 948 1 11,411 - - - 940 940 Income before taxes on income 12,694 4,057 3,295 20,046 3,710 3,830 1,716 4,390 13,646 Income tax expense 161 154 129 444 137 117 149 95 498 Net income $ 12,533 $ 3,903 $ 3,166 $ 19,602 $ 3,573 $ 3,713 $ 1,567 $ 4,295 $ 13,148 Weighted average number of shares outstanding, basic and diluted 100,187 100,187 100,187 100,187 100,187 100,187 100,187 100,187 100,187 Net income per share, basic and diluted $ 0.13 $ 0.04 $ 0.03 $ 0.20 $ 0.04 $ 0.04 $ 0.02 $ 0.04 $ 0.13 September 30, 2015 5

Condensed Consolidated Balance Sheets (in thousands) March 31, June 30, September 30, March 31, June 30, September 30, December 31, 2015 2015 2015 2014 2014 2014 2014 Assets: Real estate assets: Land $ 174,707 $ 180,271 $ 180,271 $ 185,479 $ 185,479 $ 185,479 $ 183,930 Buildings and improvements 1,581,524 1,636,444 1,639,869 1,605,808 1,609,747 1,613,699 1,604,984 Fixtures and equipment 1,724 1,800 1,882 1,296 1,395 1,633 1,677 1,757,955 1,818,515 1,822,022 1,792,583 1,796,621 1,800,811 1,790,591 Less accumulated depreciation 271,058 279,172 291,331 234,447 246,658 258,799 266,284 Real estate assets, net 1,486,897 1,539,343 1,530,691 1,558,136 1,549,963 1,542,012 1,524,307 Acquired real estate leases, net 124,337 126,926 117,272 172,262 161,519 149,019 138,714 Investment in non-consolidated REITs 78,228 78,164 77,853 79,983 79,405 78,907 78,611 Cash and cash equivalents 14,945 15,841 19,100 20,031 18,455 15,930 7,519 Restricted cash 56 48 34 688 728 707 742 Tenant rent receivables, net 4,587 2,886 3,548 6,035 2,867 2,865 4,733 Straight-line rent receivable, net 45,498 46,168 47,330 44,392 46,021 46,737 47,021 Prepaid expenses and other assets 14,114 9,658 10,324 9,954 9,716 9,768 10,901 Related party mortgage loan receivable 93,641 93,641 93,641 101,916 88,436 88,436 93,641 Other assets: derivative asset 774 918 - 4,801 2,626 4,582 3,020 Deferred leasing commissions, net 26,335 26,508 26,587 27,477 28,861 28,354 27,181 Total assets $ 1,889,412 $ 1,940,101 $ 1,926,380 $ 2,025,675 $ 1,988,597 $ 1,967,317 $ 1,936,390 Liabilities: Bank note payable $ 240,000 $ 300,000 $ 300,000 $ 316,500 $ 296,500 $ 285,000 $ 268,000 Term loan payable 620,000 620,000 620,000 620,000 620,000 620,000 620,000 Accounts payable and accrued expenses 36,065 39,199 42,164 34,390 34,590 40,228 42,561 Accrued compensation 1,241 2,327 3,236 1,027 2,052 2,863 3,758 Tenant security deposits 4,019 4,315 4,349 4,258 4,259 4,331 4,248 Other liabilities: derivative termination value 9,836 7,632 12,096 3,825 5,985 4,847 7,268 Acquired unfavorable real estate leases, net 9,921 11,082 10,241 13,273 12,467 11,679 10,908 Total liabilities 921,082 984,555 992,086 993,273 975,853 968,948 956,743 Commitments and contingencies 6WRFNKROGHUV (Preferred stock - - - - - - -Common stock 10 10 10 10 10 10 10 Additional paid-in capital 1,273,556 1,273,556 1,273,556 1,273,556 1,273,556 1,273,556 1,273,556 Accumulated other comprehensive income (loss) (9,062) (6,714) (12,096) 976 (3,359) (265) (4,248) Accumulated distributions in excess of accumulated earnings (296,174) (311,306) (327,176) (242,140) (257,463) (274,932) (289,671) s968,330 955,546 934,294 1,032,402 1,012,744 998,369 979,647 $ 1,889,412 $ 1,940,101 $ 1,926,380 $ 2,025,675 $ 1,988,597 $ 1,967,317 $ 1,936,390 September 30, 2015 6

Condensed Consolidated Statements of Cash Flows (in thousands) Nine Months ended September 30, Twelve Months ended December 31 2015 2014 2014 2013 Cash flows from operating activities: Net income $ 19,602 $ 8,853 $ 13,148 $ 19,827 Adjustments to reconcile net income to net cash provided by operating activities: Depreciation and amortization expense 70,340 74,237 97,916 81,267 Amortization of above market lease (96) 560 635 (365) Gain on sale of properties, less applicable income tax (11,411) - (940) (2,158) Equity in earnings (losses) from non-consolidated REITs 644 1,491 1,760 1,358 Increase in allowance for doubtful accounts (125) 125 275 (1,250) Changes in operating assets and liabilities: Restricted cash 708 (64) (99) (68) Tenant rent receivables 1,310 2,112 94 (2,103) Straight-line rents (1,573) (4,038) (4,737) (5,782) Lease acquisition costs (463) (438) (440) (1,146) Prepaid expenses and other assets (997) (106) 700 (1,547) Accounts payable and accrued expenses (603) (2,133) 206 11,137 Accrued compensation (522) (122) 773 445 Tenant security deposits 101 304 222 1,538 Payment of deferred leasing commissions (4,254) (4,854) (6,347) (9,125) Net cash provided by operating activities 72,661 75,927 103,166 92,028 Cash flows from investing activities: Property acquisitions (66,104) - - (454,447) Acquired real estate leases (10,604) - - (100,143) Property improvements, fixtures and equipment (15,005) (12,403) (18,370) (19,120) Office computers and furniture - - (191) (355) Investment in non-consolidated REITs - - - 4,858 Distributions in excess of earnings from non-consolidated REITs 81 81 107 108 Investment in related party mortgage loan receivable - (2,570) (11,170) (8,200) Repayment of related party mortgage loan receivable - 13,880 17,275 2,350 Changes in deposits on real estate assets - - - - Proceeds received on sales of real estate assets 55,659 - 14,192 12,301 Net cash provided by (used in) investing activities (35,973) (1,012) 1,843 (562,648) Cash flows from financing activities: Distributions to stockholders (57,107) (57,108) (76,142) (69,588) Proceeds (costs) from equity offering, net - - - 230,682 Borrowings under bank note payable 95,000 10,000 15,000 160,000 Repayments of bank note payable (63,000) (31,500) (53,500) (70,250) Borrowing (repayment) of term loan payable, net - - - 220,000 Deferred Financing Costs - - (2,471) (1,868) Net cash provided by (used in) financing activities (25,107) (78,608) (117,113) 468,976 Net decreases in cash and cash equivalents 11,581 (3,693) (12,104) (1,644) Cash and cash equivalents, beginning of period 7,519 19,623 19,623 21,267 Cash and cash equivalents, end of period $ 19,100 $ 15,930 $ 7,519 $ 19,623 September 30, 2015 7

Property Net Operating Income (NOI)* with Same Store Comparison (in thousands) (in thousands) Rentable Nine Months Nine Months Square Feet Three Months Ended Ended Three Months Ended Ended Inc % Region or RSF 31-Mar-15 30-Jun-15 30-Sep-15 30-Sep-15 31-Mar-14 30-Jun-14 30-Sep-14 30-Sep-14 (Dec) Change East 1,333 $ 4,736 $ 4,648 $ 4,703 $ 14,087 $ 4,577 $ 4,655 $ 4,600 $ 13,832 $ 255 1.8% MidWest 1,531 3,469 3,563 3,547 10,579 4,586 4,541 4,610 13,737 (3,158) -23.0% South 4,026 15,781 15,995 15,971 47,747 16,796 16,183 16,370 49,349 (1,602) -3.2% West 2,309 8,216 8,571 8,523 25,310 9,388 9,290 8,522 27,200 (1,890) -6.9% Same Store 9,199 32,202 32,777 32,744 97,723 35,347 34,669 34,102 104,118 (6,395) -6.1% Acquisitions 442 - 1,057 1,067 2,124 - - - - 2,124 2.0% Property NOI from the continuing portfolio 9,641 32,202 33,834 33,811 99,847 35,347 34,669 34,102 104,118 (4,271) -4.1% Dispositions 822 61 6 889 1,226 1,257 1,351 3,834 (2,945) -2.6% Property NOI $ 33,024 $ 33,895 $ 33,817 $ 100,736 $ 36,573 $ 35,926 $ 35,453 $ 107,952 $ (7,216) -6.7% Same Store $ 32,202 $ 32,777 $ 32,744 $ 97,723 $ 35,347 $ 34,669 $ 34,102 $ 104,118 $ (6,395) -6.1% Less Nonrecurring Items in NOI (a) 75 81 419 575 707 287 173 1,167 (592) 0.5% Comparative Same Store $ 32,127 $ 32,696 $ 32,325 $ 97,148 $ 34,640 $ 34,382 $ 33,929 $ 102,951 $ (5,803) -5.6% (a) Nonrecurring Items in NOI include proceeds from bankruptcies, lease termination fees or other significant nonrecurring income or expenses, which may affect comparability. * See page 11 for a reconciliation of Net Income to Property NOI and the Appendix for Definitions of Non-GAAP Measures beginning on page 27. Property NOI Excludes NOI from investments in and interest income from secured loans to non-consolidated REITs. September 30, 2015 8

FFO & AFFO Reconciliation (in thousands, except per share amounts) For the Nine For the For the Three Months Ended Months Ended For the Three Months Ended Year Ended 31-Mar-15 30-Jun-15 30-Sep-15 30-Sep-15 31-Mar-14 30-Jun-14 30-Sep-14 31-Dec-14 31-Dec-14 Net income $ 12,533 $ 3,903 $ 3,166 $ 19,602 $ 3,573 $ 3,713 $ 1,567 $ 4,295 $ 13,148 Gain (loss) on sale, less applicable income tax (10,462) (948) (1) (11,411) - - - (940) (940) GAAP income from non-consolidated REITs 322 38 284 644 484 552 455 269 1,760 FFO from non-consolidated REITs 601 885 645 2,131 419 351 508 652 1,930 Depreciation & amortization 22,678 23,168 22,848 68,694 24,289 23,638 25,374 23,249 96,550 NAREIT FFO* 25,672 27,046 26,942 79,660 28,765 28,254 27,904 27,525 112,448 Acquisition costs - 142 12 154 14 - - - 14 Funds From Operations (FFO)* $ 25,672 $ 27,188 $ 26,954 $ 79,814 $ 28,779 $ 28,254 $ 27,904 $ 27,525 $ 112,462 Adjusted Funds From Operations (AFFO)* Funds From Operations (FFO)* $ 25,672 $ 27,188 $ 26,954 $ 79,814 $ 28,779 $ 28,254 $ 27,904 $ 27,525 $ 112,462 Reverse FFO from non-consolidated REITs (601) (885) (645) (2,131) (419) (351) (508) (652) (1,930) Distributions from non-consolidated REITs 27 27 27 81 27 27 27 26 107 Amortization of deferred financing costs 517 517 516 1,550 499 499 498 506 2,002 Straight-line rent (69) (574) (930) (1,573) (1,783) (1,541) (714) (698) (4,736) Tenant improvements (2,936) (3,420) (1,794) (8,150) (1,132) (1,837) (2,612) (4,244) (9,825) Leasing commissions (830) (1,539) (1,490) (3,859) (1,080) (2,786) (577) (1,405) (5,848) Non-investment capex (643) (1,418) (1,090) (3,151) (364) (1,621) (700) (851) (3,536) Adjusted Funds From Operations (AFFO)* $ 21,137 $ 19,896 $ 21,548 $ 62,581 $ 24,527 $ 20,644 $ 23,318 $ 20,207 $ 88,696 Per Share Data: EPS $ 0.13 $ 0.04 $ 0.03 $ 0.20 $ 0.04 $ 0.04 $ 0.02 $ 0.04 $ 0.13 FFO* 0.26 0.27 0.27 0.80 0.29 0.28 0.28 0.27 1.12 AFFO* 0.21 0.20 0.22 0.62 0.24 0.21 0.23 0.20 0.89 Weighted Average Shares (basic and diluted) 100,187 100,187 100,187 100,187 100,187 100,187 100,187 100,187 100,187 * See the Appendix for Definitions of these Non-GAAP Measures beginning on page 27. September 30, 2015 9

EBITDA Reconciliation (in thousands, except ratio amounts) Nine Months For the Three Months Ended Ended For the Three Months Ended Year Ended 31-Mar-15 30-Jun-15 30-Sep-15 30-Sep-15 31-Mar-14 30-Jun-14 30-Sep-14 31-Dec-14 31-Dec-14 Net income $ 12,533 $ 3,903 $ 3,166 $ 19,602 $ 3,573 $ 3,713 $ 1,567 $ 4,295 $ 13,148 Interest expense 6,187 6,365 6,425 18,977 7,176 6,891 6,883 6,483 27,433 Depreciation and amortization 22,678 23,168 22,848 68,694 24,289 23,638 25,374 23,249 96,550 Income taxes 161 154 129 444 137 117 149 95 498 EBITDA 41,559 33,590 32,568 107,717 35,175 34,359 33,973 34,122 137,629 Excluding (gain) loss on sale, less applicable income tax (10,462) (948) (1) (11,411) - - - (940) (940) Adjusted EBITDA $ 31,097 $ 32,642 $ 32,567 $ 96,306 $ 35,175 $ 34,359 $ 33,973 $ 33,182 $ 136,689 Interest expense $ 6,187 $ 6,365 $ 6,425 $ 18,977 $ 7,176 $ 6,891 $ 6,883 $ 6,483 $ 27,433 Scheduled principal payments - - - - - - - - - Interest and scheduled principal payments $ 6,187 $ 6,365 $ 6,425 $ 18,977 $ 7,176 $ 6,891 $ 6,883 $ 6,483 $ 27,433 Interest coverage ratio 5.03 5.13 5.07 5.07 4.90 4.99 4.94 5.12 4.98 Debt service coverage ratio 5.03 5.13 5.07 5.07 4.90 4.99 4.94 5.12 4.98 Debt $ 860,000 $ 920,000 $ 920,000 $ 936,500 $ 916,500 $ 905,000 $ 888,000 Adjusted EBITDA 31,097 32,642 32,567 35,175 34,359 33,973 33,182 Annualized 124,388 130,568 130,268 140,700 137,436 135,892 132,728 Debt-to-EBITDA 6.9 7.0 7.1 6.7 6.7 6.7 6.7 * See the Appendix for Definitions of these Non-GAAP Measures beginning on page 27. Amounts in the EBITDA reconciliation do not reflect our proportionate share of interest expense, depreciation, amortization, income taxes, gains or losses on sales and debt from our investments in non-consolidated REITs , which are accounted for under the equity method. September 30, 2015 10

 Reconciliation of Net Income to Property NOI* (in thousands) Reconciliation to Net income Nine Months Nine Months Three Months Ended Ended Three Months Ended Ended 31-Mar-15 30-Jun-15 30-Sep-15 30-Sep-15 31-Mar-14 30-Jun-14 30-Sep-14 30-Sep-14 Net Income $ 12,533 $ 3,903 $ 3,166 $ 19,602 $ 3,573 $ 3,713 $ 1,567 $ 8,853 Add (deduct): Gain on sale of properties, less applicable income taxes (10,462) (948) (1) (11,411) - - - - Management fee income (643) (559) (621) (1,823) (646) (682) (649) (1,977) Depreciation and amortization 22,672 23,207 22,911 68,790 24,300 23,563 24,878 72,741 Amortization of above/below market leases 6 (39) (63) (96) (11) 74 497 560 Selling, general and administrative 3,691 3,401 3,071 10,163 3,272 3,148 3,071 9,491 Interest expense 6,187 6,365 6,426 18,978 7,176 6,891 6,883 20,950 Interest income (1,262) (1,278) (1,293) (3,833) (1,410) (1,408) (1,216) (4,034) Equity in losses of - - non-consolidated REITs 322 38 284 644 484 552 455 1,491 Non-property specific items, net (20) (195) (63) (278) (165) 75 (33) (123) Property NOI $ 33,024 $ 33,895 $ 33,817 $ 100,736 $ 36,573 $ 35,926 $ 35,453 $ 107,952 * See the Appendix for Definition of Non-GAAP Measures beginning on page 27. September 30, 2015 11

Debt Summary (in thousands) Maximum Amount Interest Interest Maturity Amount Drawn at Rate Rate at Facility Date of Loan 30-Sep-15 Components 30-Sep-15 Fee BAML Revolver 29-Oct-18 $ 500,000 $ 300,000 L+1.25% 1.45% 0.25% BAML Term Loan 27-Sep-17 400,000 400,000 0.75% + 1.45% 2.20% BMO Term Loan 26-Aug-20 220,000 220,000 2.32% + 1.65% 3.97% $ 1,120,000 $ 920,000 2.38% (a) Interest rate excludes amortization of deferred financing costs and facility fees, see notes below On October 29, 2014, we amended and restated our bank facility we call the BAML Credit Facility, which has a total of $900 million available and is comprised of a revolver that we can borrow up to $500 million on, which we call the BAML Revolver and a term loan for $400 million that we call the BAML Term Loan. On August 26, 2013, we entered into a term loan we call the BMO Term Loan and borrowed $220 million. Additional information about these loans are in the footnotes to our financial statements. Pricing is based on our credit rating for the BAML Revolver, BAML Term Loan and the BMO Term Loan. Our credit rating as of September 30, 2015 was Baa3 from Moody’s. The BAML Revolver is priced based on our current credit rating at a spread of 1.25%, which was an interest rate of 1.44% as of September 30, 2015. The BAML Revolver is also subject to a facility fee based on our credit rating, which was 25 bps or approximately $1.25 million per year. The BAML Term Loan has LIBOR fixed at 0.75% for five years. At our credit rating, the spread for the BAML Term Loan is 1.45%, so our interest rate is 2.20%. The BMO Term Loan has fixed LIBOR at 2.32% for seven years. At our credit rating, the spread over LIBOR is 1.65%, so our interest rate is 3.97%. We incurred financing costs to close the BAML Revolver, BAML Term Loan and the credit facilities that preceded them. We also incurred financing costs to close the BMO Term Loan. These costs are deferred and amortized into interest expense during the terms of the loans. The annual run rate for amortization to interest expense from deferred financing costs is approximately $2.1 million. The BAML Revolver can be extended for 1 year at the Company’s option upon payment of fees and includes an accordion feature that allows for up to $250 million of additional borrowing capacity. The BMO Term Loan includes an accordion feature that allows for up to $50 million of additional borrowing capacity. The accordion features are subject to receipt of lender commitments and satisfaction of certain customary conditions. September 30, 2015 12

Capital Analysis (in thousands, except per share amounts) 31-Mar-15 30-Jun-15 30-Sep-15 31-Mar-14 30-Jun-14 30-Sep-14 31-Dec-14 Market Data: Shares Outstanding 100,187 100,187 100,187 100,187 100,187 100,187 100,187 Closing market price per share $ 12.82 $ 11.31 $ 10.75 $ 12.60 $ 12.58 $ 11.22 $ 12.27 Market capitalization $ 1,284,403 $ 1,133,120 $ 1,077,015 $ 1,262,361 $ 1,260,358 $ 1,124,103 $ 1,229,299 Total Debt 860,000 920,000 920,000 936,500 916,500 905,000 888,000 Total Market Capitalization $ 2,144,403 $ 2,053,120 $ 1,997,015 $ 2,198,861 $ 2,176,858 $ 2,029,103 $ 2,117,299 Dividend Data: Total dividends paid $ 19,036 $ 19,035 $ 19,035 $ 19,036 $ 19,035 $ 19,036 $ 19,036 Common dividend per share $ 0.19 $ 0.19 $ 0.19 $ 0.19 $ 0.19 $ 0.19 $ 0.19 Quarterly dividend as a % of FFO* 73.1% 70.4% 70.4% 65.5% 67.9% 67.9% 70.4% Liquidity: Cash and cash equivalents $ 14,946 $ 15,841 $ 19,100 $ 20,031 $ 18,455 $ 15,930 $ 7,519 Revolving credit facilities: Gross potential available under the BAML Credit Facility 900,000 900,000 900,000 900,000 900,000 900,000 900,000 Less: Outstanding balance (640,000) (700,000) (700,000) (716,500) (696,500) (685,000) (668,000) Total Liquidity $ 274,946 $ 215,841 $ 219,100 $ 203,531 $ 221,955 $ 230,930 $ 239,519 *See page 9 for a reconciliation of Net Income to FFO and the Appendix for Definitions of Non-GAAP Measures beginning on page 27. September 30, 2015 13

Portfolio Overview As of the Quarter Ended Portfolio Breakdown by 30-Sep-15 30-Jun-15 31-Mar-15 31-Dec-14 30-Sep-14 FSP Participation Owned portfolio of commercial real estate: Owned Properties Number of properties 36 36 36 38 39 Square feet 9,640,904 9,639,740 9,310,131 9,580,057 9,690,361 Non-Consolidated Properties Leased percentage 90.5% 90.6% 90.4% 92.8% 93.3% Managed Single Asset REITs (SARs) Investments in non-consolidated commercial real estate: 11.9% Number of properties 2 2 2 2 2 Square feet 1,396,071 1,396,071 1,396,071 1,395,780 1,395,500 Leased percentage 71.2% 69.7% 70.1% 71.3% 71.0% 11.1% Single Asset REITs (SARs) managed: Number of properties 7 7 7 8 9 Square feet 1,487,026 1,487,026 1,488,003 1,897,801 2,036,572 Leased percentage 77.0% 73.5% 73.4% 84.7% 86.6% Total owned (a) , investments and managed properties: Number of properties 45 45 45 48 50 Square feet 12,524,001 12,522,837 12,194,205 12,873,638 13,122,433 77.0 % Leased percentage 86.8% 86.3% 86.0% 89.3% 89.9% September 30, 2015 14

Owned Portfolio Overview Percent Wtd Ave (a) GAAP (b) Percent Wtd Ave (a) GAAP (b) MSA / Property Name City State Square Feet Leased Occupied Rent MSA / Property Name City State Square Feet Leased Occupied Rent East Region Midwest Region Baltimore Chicago East Baltimore Baltimore MD 325,445 85.4% 81.3% $ 23.40 Northwest Point Elk Grove Village IL 176,848 100.0% 100.0% $ 24.73 909 Davis Street Evanston IL 195,245 100.0% 98.9% $ 35.20 Washington, D.C. Meadow Point Chantilly VA 138,537 100.0% 94.3% $ 27.31 Indianapolis Stonecroft Chantilly VA 111,469 100.0% 100.0% $ 37.64 River Crossing Indianapolis IN 205,059 90.6% 94.7% $ 20.43 Loudoun Tech Center Dulles VA 136,658 92.0% 92.0% $ 17.88 St. Louis Richmond Timberlake Chesterfield MO 234,023 93.8% 54.7% $ 21.15 Innsbrook Glen Allen VA 298,456 99.9% 99.9% $ 18.73 Timberlake East Chesterfield MO 116,197 43.7% 28.5% $ 21.96 Lakeside Crossing Maryland Heights MO 127,778 100.0% 100.0% $ 24.33 Charlotte Forest Park Charlotte NC 62,212 100.0% 100.0% $ 13.82 Minneapolis 121 South 8th Street Minneapolis MN 475,694 90.8% 89.9% $ 15.49 Raleigh-Durham Emperor Boulevard Durham NC 259,531 100.0% 100.0% $ 35.93 Midwest Region Total 1,530,844 90.7% 83.7% $ 22.10 East Region Total 1,332,308 95.6% 94.0% $ 25.53 (a) Weighted Occupied Percentage for the nine months ended September 30, 2015. (b) Weighted Average GAAP Rent per Occupied Square Foot. September 30, 2015 15

Owned Portfolio Overview Percent Wtd Ave (a) GAAP (b) Percent Wtd Ave (a) GAAP (b) MSA / Property Name City State Square Feet Leased Occupied Rent MSA / Property Name City State Square Feet Leased Occupied Rent South Region West Region Dallas-Fort Worth Seattle Legacy Tennyson Center Plano TX 202,600 100.0% 100.0% $ 17.37 Federal Way Federal Way WA 117,010 58.9% 58.1% $ 18.58 One Legacy Circle Plano TX 214,110 100.0% 100.0% $ 33.36 Addison Circle Addison TX 290,041 93.4% 86.1% $ 24.79 San Francisco-San Jose-Oakland Collins Crossing Richardson TX 300,887 100.0% 99.5% $ 24.54 Hillview Center Milpitas CA 36,288 100.0% 100.0% $ 16.33 Liberty Plaza Addison TX 218,934 82.5% 86.3% $ 20.76 Montague Business Center San Jose CA 145,951 81.1% 81.1% $ 16.55 Houston Denver Park Ten Houston TX 157,460 63.1% 63.1% $ 31.56 380 Interlocken Broomfield CO 240,185 97.1% 96.3% $ 29.54 Eldridge Green Houston TX 248,399 100.0% 100.0% $ 31.28 1999 Broadway Denver CO 676,379 82.5% 85.8% $ 32.23 Park Ten Phase II Houston TX 156,746 100.0% 100.0% $ 31.53 Greenwood Plaza Englewood CO 196,236 100.0% 100.0% $ 24.78 Westchase I & II Houston TX 629,025 90.2% 94.2% $ 33.99 390 Interlocken Broomfield CO 241,516 85.3% 71.7% $ 28.29 1001 17th Street Denver CO 655,420 86.3% 84.2% $ 34.39 Miami-Ft. Lauderdale-West Palm Beach Blue Lagoon Drive Miami FL 212,619 100.0% 100.0% $ 22.54 Atlanta One Overton Place Atlanta GA 387,267 85.0% 80.1% $ 24.40 West Region Total 2,308,985 85.9% 84.7% $ 29.70 One Ravinia Atlanta GA 386,603 94.8% 95.1% $ 22.91 Two Ravinia Atlanta GA 442,130 77.4% 75.8% $ 24.98 999 Peachtree Atlanta GA 621,946 94.7% 95.3% $ 30.14 South Region Total 4,468,767 83.7% 91.1% $ 27.30 Total Owned 9,640,904 90.5% 88.8% $ 26.81 (a) Weighted Occupied Percentage for the nine months ended September 30, 2015. (b) Weighted Average GAAP Rent per Occupied Square Foot. September 30, 2015 16

Managed Portfolio Overview MSA / Property Name City State Square Feet MSA / Property Name City State Square Feet Southeast Region Midwest Region Columbia Chicago 1441 Main Street Columbia SC 264,857 (a) East Wacker Chicago IL 861,000 Atlanta Indianapolis Satellite Place Duluth GA 134,785 Monument Circle Indianapolis IN 213,760 Southeast Region Total 399,642 St. Louis Lakeside Crossing II Maryland Heights MO 116,000 Southwest Region Kansas City Houston (b) Grand Boulevard Kansas City MO 535,071 Energy Tower I Houston TX 325,797 Cincinnati Denver Centre Pointe V West Chester OH 135,936 385 Interlocken Broomfield CO 295,891 Southwest Region Total 621,688 Midwest Region Total 1,861,767 Total Managed 2,883,097 Total Owned & Managed 12,524,001 (a) FSP has a Preferred Share Interest of 43.7% in the entity that owns this property. (b) FSP has a Preferred Share Interest of 27.0% in the entity that owns this property. September 30, 2015 17

Tenants by Industry (By Square Feet) Oil & Gas 16.55% Other 16.86% Medical Professionals & Social Services 2.81% Restaurants 3.00% Banking 10.18% Medical Research 3.06% Insurance 3.17% Legal Services 8.57% Architecture & Engineering 3.47% Real Estate 3.57% General Business Services 3.75% IT & Computer Services 8.51% Communications 4.00% Government 5.62% Professional Services 6.87% Oil & Gas 16.55% Banking 10.18% Legal Services 8.57% IT & Computer Services 8.51% Professional Services 6.87% Government 5.62% Communications 4.00% General Business Services 3.75% Real Estate 3.57% Architecture & Engineering 3.47% Insurance 3.17% Medical Research 3.06% Restaurants 3.00% Medical Professionals & Social Services 2.81% Other 16.86% September 30, 2015 18

 20 Largest Tenants with Annualized Rent and Remaining Term (Owned Portfolio) Remaining Aggregate Annualized % of Aggregate Tenant Number of Lease Term Leased % of Total Rent Leased Name Leases in Months Square Feet Square Feet (in 000's) Annualized Rent 1 TCF National Bank 2 3 263,111 2.7% $ 2,997,573 1.3% 2 Quintiles Transnational Corp 1 42 259,531 2.7% 9,067,770 4.0% 3 CITGO Petroleum Corporation 1 77 248,399 2.6% 7,904,056 3.5% 4 Newfield Exploration Company 1 77 234,495 2.4% 8,630,672 3.9% 5 US Government (a) 5 9, 11, 32, 46, 60 223,433 2.3% 7,225,672 3.2% 6 Sutherland Asbill Brennan LLP 1 55 222,422 2.3% 6,823,317 3.0% 7 Burger King Corporation 1 36 212,619 2.2% 5,134,749 2.3% 8 Denbury Onshore, LLC (b) 2 10, 46 202,600 2.1% 3,510,042 1.6% 9 SunTrust Bank (c) 3 8, 134, 72 182,888 1.9% 3,736,826 1.7% 10 Citicorp Credit Services, Inc 1 15 176,848 1.8% 4,612,196 2.1% 11 T-Mobile South, LLC dba T-Mobile 1 41 151,792 1.6% 3,635,589 1.6% 12 Houghton Mifflin Harcourt Publishing Company 1 18 150,050 1.6% 6,243,052 2.8% 13 Petrobras America, Inc. 1 50 144,813 1.5% 5,337,807 2.4% 14 Murphy Exploration & Production Company 1 19 144,677 1.5% 4,718,321 2.1% 15 Argo Data Resource Corporation 1 95 140,246 1.5% 3,718,923 1.7% 16 Monsanto Company 1 52 127,778 1.3% 3,019,394 1.3% 17 Federal National Mortgage Association 1 12 123,144 1.3% 2,695,622 1.2% 18 Vail Corp d/b/a Vail Resorts (d) 2 42, 90 122,232 1.3% 3,478,650 1.6% 19 Kaiser Foundation Health Plan 1 104 120,979 1.3% 3,091,345 1.4% 20 Centene Management Company, LLC (e) 1 93 117,618 1.2% - - Total 3,569,675 37.1% $ 95,581,575 42.7% (a) Includes 180,444 and 27,398 square feet which expire in 2018 & 2017, respectively. The remaining 15,591 square feet expire between 2016 - 2020. (b) Includes 102,600 square feet which expire 7/31/16 and 100,000 square feet that expire 7/31/19. (c) Includes 23,217 square feet, which expire 4/30/16 and 32,171 square feet, which expire 10/31/26. The remaining 127,500 square feet expire 9/30/21. (d) Includes 38,293 square feet which expire March 31, 2019. The remaining 83,939 square feet expire March 31, 2023. (e) The lease was executed June 30, 2015 and rent has not commenced. September 30, 2015 19

Leasing Activity (Owned Portfolio) Nine Months Year Year Ended Ended Ended Leasing Activity 30-Sep-15 31-Dec-14 31-Dec-13 (in Square Feet - SF) New leasing 262,000 149,000 267,000 Renewals 454,000 635,000 645,000 716,000 784,000 912,000 Other information per SF (Activity on a year-to-date basis) GAAP Rents on leasing $ 26.70 $ 26.89 $ 23.33 Weighted average lease term 5.2 Years 6.25 Years 7.2 Years Increase over average GAAP rents in prior year 12.9% 11.8% 8.0% Average free rent 3 Months 3 Months 3 Months Tenant Improvements $ 16.88 $ 16.40 $ 18.25 Leasing Costs $ 6.33 $ 7.66 $ 8.48 September 30, 2015 20

Lease Expirations by Square Feet (Owned Portfolio) % of Square 2,000,000 Year Total Square Feet Feet 1,800,000 2015 69,019 0.7% 2016 1,005,764 10.4% 1,600,000 2017 1,119,778 11.6% 1,400,000 2018 996,420 10.3% 2019 1,473,328 15.3% 1,200,000 2020 859,385 8.9% 1,000,000 2021 816,955 8.5% 2022 992,342 10.3% 800,000 2023 596,384 6.2% 600,000 2024 273,770 2.9% 2025 320,471 3.3% 400,000 2026 202,054 2.1% 200,000 Vacant 915,234 9.5% 0 Total 9,640,904 100.0% 2015 2017 2019 2021 2023 2025 Total Square Feet September 30, 2015 21

 Lease Expirations with Annualized Rent per Square Foot (Owned Portfolio ) Rentable Annualized Percentage Number of Square Rent of Total Year of Leases Footage Annualized Per Square Annualized Lease Expiring Subject to Rent Under Foot Under Rent Under Expiration Within the Expiring Expiring Expiring Expiring Cumulative December 31, Year (a) Leases Leases (b) Leases Leases Total 2015 21 (c) 69,019 $ 1,996,865 $ 28.93 0.9% 0.9% 2016 65 1,005,764 21,309,028 21.19 9.5% 10.4% 2017 71 1,119,778 32,867,345 29.35 14.7% 25.1% 2018 74 996,420 29,078,109 29.18 13.0% 38.1% 2019 62 1,473,328 41,082,293 27.88 18.4% 56.4% 2020 58 859,385 22,049,788 25.66 9.8% 66.3% 2021 26 816,955 19,713,951 24.13 8.8% 75.1% 2022 25 992,342 28,891,248 29.11 12.9% 88.0% 2023 19 596,384 11,562,784 19.39 5.2% 93.2% 2024 7 273,770 6,862,689 25.07 3.1% 96.2% 2025 and thereafter 17 522,525 (d) 8,447,095 16.17 3.8% 100.0% 445 8,725,670 $ 223,861,194 $ 25.66 100.0% Vacancies as of 9/30/15 915,234 Total Portfolio Square Footage 9,640,904 (a) The number of leases approximates the number of tenants. Tenants with lease maturities in different years are included in annual totals for each lease. Tenants may have multiple leases in the same year. (b) Annualized rent represents the monthly rent charged, including tenant reimbursements, for each lease in effect at September 30, 2015 mulitplied by 12. Tenant reimbursements generally include payment of real estate taxes, operating expenses and common area maintenance and utility charges. (c) Includes 13 leases that are month-to-month. (d) Includes 68,281 square feet that are non-revenue producing building amenities. September 30, 2015 22

Capital Expenditures (in thousands) Nine Months For the Three Months Ended Ended 31-Mar-15 30-Jun-15 30-Sep-15 30-Sep-15 Tenant improvements $ 2,936 $ 3,420 $ 1,794 $ 8,150 Deferred leasing costs 830 1,539 1,490 3,859 Non-investment capex 643 1,418 1,090 3,151 Recurring Capital Expenditures 4,409 6,377 4,374 15,160 1st generation leasing 1,934 712 451 3,097 Investment capex 230 243 558 1,031 121 South 8thStreet, Minneapolis, MN Total Capital Expenditures $ 6,573 $ 7,332 $ 5,383 $ 19,288 For the Three Months Ended Year ended 31-Mar-14 30-Jun-14 30-Sep-14 31-Dec-14 31-Dec-14 Tenant improvements $ 1,132 $ 1,837 $ 2,612 $ 4,244 $ 9,825 Deferred leasing costs 1,080 2,786 577 1,405 5,848 Non-investment capex 364 1,621 700 851 3,536 Recurring Capital Expenditures 2,576 6,244 3,889 6,500 19,209 1st generation leasing 33 9 394 580 1,016 Investment capex 755 580 244 516 2,095 Total Capital Expenditures $ 3,364 $ 6,833 $ 4,527 $ 7,596 $ 22,320 September 30, 2015 23

Transaction Activity (in thousands except for Square feet) Recent Acquisitions: Purchase Price City State Square Feet Date Acquired 2015 Two Ravinia Atlanta GA 442,130 4/8/15 $ 78,000 2013 1999 Broadway Denver CO 673,793 5/22/13 $ 183,000 999 Peachtree Atlanta GA 621,946 7/1/13 157,900 1001 17th Street Denver CO 655,420 8/28/13 217,000 2012 One Ravinia Atlanta GA 386,603 7/31/12 $ 52,750 Westchase Houston TX 629,025 11/1/12 154,750 Recent Dispositions: Gross Sales Gains City State Square Feet Date Sold Proceeds on Sales 2015 Willow Bend Plano TX 117,050 2/23/15 $ 20,750 $ 1,462 Eden Bluff Eden Prairie MN 153,028 3/31/15 28,000 9,000 Park Seneca Charlotte NC 109,699 5/13/15 8,150 948 2014 Centennial Colorado Springs CO 110,405 12/3/14 $ 15,500 $ 940 2013 East Renner Road Richardson TX 122,300 10/29/13 $ 12,475 $ 2,169 September 30, 2015 24

Loan Portfolio of Secured Real Estate (in thousands) (dollars in thousands) Maximum Amount Interest Maturity Amount Drawn at Interest Draw Rate at Sponsored REIT Location Date of Loan 30-Sep-15 Rate (1) Fee (2) 30-Sep-15 Secured revolving lines of credit FSP Satellite Place Corp. Duluth, GA 31-Mar-17 $ 5,500 $ 5,500 L+4.4% 0.5% 4.60% FSP 1441 Main Street Corp. Columbia, SC 31-Mar-16 10,800 9,000 L+4.4% 0.5% 4.60% FSP Energy Tower I Corp. Houston, TX 30-Jun-17 20,000 8,600 L+5.0% 0.5% 5.20% Secured construction loan FSP 385 Interlocken Development Corp. Broomfield, CO 30-Apr-16 42,000 37,541 L+4.4% n/a 4.60% Mortgage loan secured by property FSP Energy Tower I Corp. Houston, TX 30-Jun-17 33,000 33,000 6.41% n/a 6.41% $ 111,300 $ 93,641 (1) The interest rate is 30-day LIBOR rate plus the additional rate indicated, otherwise a fixed rate. (2) The draw fee is a percentage of each new advance, and is paid at the time of each new draw. September 30, 2015 25

Net Asset Value Components (in thousands except per share data) As of Assets: Other information: 30-Sep-15 Loans outstanding on secured RE $ 93,641 Leased SF to be FFO producing Total Market Capitalization Values Investments in SARs (book basis) 77,853 During 2015 (in 000's) 74 Shares outstanding 100,187.4 Straight-line rent receivable 47,330 Closing price $ 10.75 Asset held for sale - Straight-line rental revenue current quarter $ 930 Market capitalization $ 1,077,015 Cash and cash equivalents 19,100 Debt 920,000 Restricted cash 34 Management fee income current quarter $ 177 Total Market Capitalization $ 1,997,015 Tenant rent receivables 3,548 Interest income from secured loans 1,294 Prepaid expenses 956 Management fees and interest income from loans $ 1,470 Office computers and furniture 551 3 Months Other assets: FFO from non-consolidated REITs - Q1 2015 (7): Ended Deferred financing costs, net 7,637 East Wacker $ 680 NOI Components 30-Sep-15 Other assets: Derivative Market Value - Grand Boulevard 205 Phoenix Tower Liquidating Trust (6) 4 Total $ 885 Same Store NOI (1) $ 32,744 Other assets 1,176 Acquisitions (1) (2) 1,067 $ 251,830 Footnotes to the components Property NOI (1) 33,811 - (1) See pages 11 & 28 for definitions and reconciliations Full quarter adjustment (3) - Liabilities: (2) Includes NOI from 3 acquisitions 2013 Stabilized portfolio $ 33,811 Debt $ 920,000 (3) Adjustment to reflect property NOI for a full quarter Accounts payable & accrued expenses 45,400 in the quarter acquired, if necessary Tenant security deposits 4,349 (4) HB3 Tax in Texas is classified as an income tax, though Financial Statement Reconciliation: Other liabilities: derivative liability 12,096 we treat it as a real estate tax in Property NOI Rental Revenue $ 60,386 $ 981,845 (5) Management & other fees are eliminated in consolidation Rental operating expenses (15,951) - but included on Property NOI Real estate taxes and insurance (9,941) (6) Expected liquidating distribution from sale of equity interest NOI on assets sold during the quarter (6) (Collection within 2 years, subject to some expenses) Taxes (4) (129) (7) We report FFO from non-consolidated REITs for the previous Management fees & other (5) (548) quarter as their financial statements are not yet complete for Property NOI (1) $ 33,811 the current quarter. September 30, 2015 26

Appendix: Non-GAAP Financial Measure Definitions Definition of Funds From Operations (“FFO”) The Company evaluates performance based on Funds From Operations, which we refer to as FFO, as management believes that FFO represents the most accurate measure of activity and is the basis for distributions paid to equity holders. The Company defines FFO as net income (computed in accordance with GAAP), excluding gains (or losses) from sales of property and acquisition costs of newly acquired properties that are not capitalized, plus depreciation and amortization, including amortization of acquired above and below market lease intangibles and impairment charges on properties or investments in non-consolidated REITs, and after adjustments to exclude equity in income or losses from, and, to include the proportionate share of FFO from, non-consolidated REITs. FFO should not be considered as an alternative to net income (determined in accordance with GAAP), nor as an indicator of the Company’s financial performance, nor as an alternative to cash flows from operating activities (determined in accordance with GAAP), nor as a measure of the Company’s liquidity, nor is it necessarily indicative of sufficient cash flow to fund all of the Company’s needs. Other real estate companies and the National Association of Real Estate Investment Trusts, or NAREIT, may define this term in a different manner. We have included the NAREIT FFO definition in our table and note that other REITs may not define FFO in accordance with the current NAREIT definition or may interpret the current NAREIT definition differently than we do. We believe that in order to facilitate a clear understanding of the results of the Company, FFO should be examined in connection with net income and cash flows from operating, investing and financing activities in the consolidated financial statements. September 30, 2015 27

Appendix: Non-GAAP Financial Measure Definitions Definition of Earnings before Interest, Taxes, Depreciation and Amortization (EBITDA) and Adjusted EBITDA EBITDA is defined as net income plus interest expense, income tax expense and depreciation and amortization expense. Adjusted EBITDA is defined as EBITDA excluding gains and losses on sales of properties or shares of equity investments or provisions for losses on assets held for sale. EBITDA and Adjusted EBITDA are not intended to represent cash flow for the period, are not presented as an alternative to operating income as an indicator of operating performance, should not be considered in isolation or as a substitute for measures of performance prepared in accordance with GAAP and are not indicative of operating income or cash provided by operating activities as determined under GAAP. EBITDA and Adjusted EBITDA are presented solely as a supplemental disclosure with respect to liquidity because the Company believes it provides useful information regarding the Company's ability to service or incur debt. Because all companies do not calculate EBITDA or Adjusted EBITDA the same way, this presentation may not be comparable to similarly titled measures of other companies. The Company believes that net income is the financial measure calculated and presented in accordance with GAAP that is most directly comparable to EBITDA and Adjusted EBITDA. Definition of Property Net Operating Income (Property NOI) The Company provides property performance based on Net Operating Income, which we refer to as NOI. Management believes that investors are interested in this information. NOI is a non-GAAP financial measure that the Company defines as net income (the most directly comparable GAAP financial measure) plus selling, general and administrative expenses, depreciation and amortization, including amortization of acquired above and below market lease intangibles and impairment charges, interest expense, less equity in earnings of nonconsolidated REITs, interest income, management fee income, gains or losses on the sale of assets and excludes non-property specific income and expenses. The information presented includes footnotes and the data is shown by region with properties owned in both periods, which we call Same Store. The Comparative Same Store results include properties held for the periods presented and exclude significant nonrecurring income such as bankruptcy settlements and lease termination fees. NOI, as defined by the Company, may not be comparable to NOI reported by other REITs that define NOI differently. NOI should not be considered an alternative to net income as an indication of our performance or to cash flows as a measure of the Company's liquidity or its ability to make distributions. September 30, 2015 28

Appendix: Non-GAAP Financial Measure Definitions Definition of Adjusted Funds From Operations (AFFO) The Company defines AFFO as the sum of (1) FFO; (2) excluding our proportionate share of FFO and including distributions received, from non-consolidated REITs; (3) excluding the effect of straight-line rent; (4) plus deferred financing costs, (5) less recurring capital expenditures that are generally for (a) maintenance of properties, which we call non-investment capex or are second generation capital expenditures. Second generation costs include re-tenanting space after a tenant vacates, which include tenant improvements and leasing commissions. We exclude development/redevelopment activities, capital expenditures planned at acquisition and costs to reposition a property. We also exclude first generation leasing costs, which are generally to fill vacant space in properties we acquire or were planned for at acquisition. AFFO should not be considered as an alternative to net income (determined in accordance with GAAP), as an indicator of the Company’s financial performance, nor as an alternative to cash flows from operating activities (determined in accordance with GAAP), nor as a measure of the Company’s liquidity, nor is it necessarily indicative of sufficient cash flow to fund all of the Company’s needs. Other real estate companies may define this term in a different manner. We believe that in order to facilitate a clear understanding of the results of the Company, AFFO should be examined in connection with net income and cash flows from operating, investing and financing activities in the consolidated financial statements. September 30, 2015 29

Investor Relations Contact: Georgia Touma (877) 686-9496 InvestorRelations@franklinstreetproperties.com One & Two RaviniaDrive, Atlanta, GA www.franklinstreetproperties.com Franklin Street Properties Corp. 401 Edgewater Place Wakefield, MA 01880 (781)557-1300