UNITED
STATES

SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM 10-K



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Commission File No. 000-52551

FSP 50 South Tenth Street Corp.

(Exact name of registrant as specified in its
charter)



|Delaware                                                        | 20-5530367                                  
|--------------------------------------------------------------- | --------------------------------------------
|(State or other jurisdiction of  incorporation or organization) | (I.R.S. Employer
        Identification No.)
|                                                                |                                             
|401 Edgewater Place, Wakefield, Massachusetts                   | 01880                                       
|(Address of principal executive offices)                        | (Zip Code)                                  



Registrant’s telephone number, including
area code:(781) 557-1300



Securities registered pursuant to Section
12(b) of the Act:None



Securities registered pursuant to Section
12(g) of the Act:



Preferred Stock, $.01 par value per share



Indicate by check mark
if the registrant is a well-known seasoned issuer, as defined in Rule 405 of the Securities Act. Yes |_|  No |X|.



Indicate by check mark
if the registrant is not required to file reports pursuant to Section 13 or 15(d) of the Act. Yes |_|  No |X|.



Indicate by check mark
whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act
of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports),
and (2) has been subject to such filing requirements for the past 90 days. Yes |X|  No |_|.



Indicate by check mark
whether the registrant has submitted electronically and posted on its corporate Website, if any, every Interactive Data File required
to be submitted and posted pursuant to Rule 405 of Regulation S-T (§ 232.405 of this chapter) during the preceding 12 months
(or for such shorter period that the registrant was required to submit and post such files). Yes |_|  No |_|.







Indicate by check mark
if disclosure of delinquent filers pursuant to Item 405 of Regulation S-K (229.405 of this chapter) is not contained herein, and
will not be contained, to the best of registrant’s knowledge, in definitive proxy or information statements incorporated
by reference in Part III of this Form 10-K or any amendment to this Form 10-K. |X|



Indicate by check mark
whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company.
See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company”
in Rule 12b-2 of the Exchange Act.



| | Large accelerated filer |_|                                               | Accelerated filer |_|        
| | ------------------------------------------------------------------------- | -----------------------------
| |                                                                           |                              
| | Non-accelerated filer   |_| (Do not check if a smaller reporting company) | Smaller reporting company |X|



Indicate by check mark whether
the registrant is a shell company (as defined in Rule 12b-2 of the Act). Yes |_|  No |X|.



As of June 30, 2010, the
aggregate fair market value of Common Stock held by non-affiliates of the registrant was $0.



The number of shares of
Common Stock outstanding was 1 and the number of shares of Preferred Stock outstanding was 700, each as of February 28, 2011.



Documents incorporated by reference:
None.





TABLE OF CONTENTS





|PART I     |                                                                                                              | 1 
|---------- | ------------------------------------------------------------------------------------------------------------ | --
|Item 1.    | Business.                                                                                                    | 1 
|Item 1A.   | Risk Factors.                                                                                                | 5 
|Item 1B.   | Unresolved Staff Comments.                                                                                   | 5 
|Item 2.    | Properties.                                                                                                  | 6 
|Item 3.    | Legal Proceedings.                                                                                           | 7 
|Item 4.    | Removed and Reserved.                                                                                        | 7 
|           |                                                                                                              |   
|PART II    |                                                                                                              | 8 
|Item 5.    | Market for Registrant’s Common Equity, Related Stockholder Matters and Issuer Purchases of Equity Securities | 8 
|Item 6.    | Selected Financial Data.                                                                                     | 8 
|Item 7.    | Management’s Discussion and Analysis of Financial Condition and Results of Operations.                       | 9 
|Item 7A.   | Quantitative and Qualitative Disclosures About Market Risk.                                                  | 14
|Item 8.    | Financial Statements and Supplementary Data.                                                                 | 14
|Item 9.    | Changes in and Disagreements With Accountants on Accounting and Financial Disclosure.                        | 14
|Item 9A.   | Controls and Procedures.                                                                                     | 15
|Item 9B.   | Other information.                                                                                           | 16
|           |                                                                                                              |   
|PART III   |                                                                                                              | 17
|Item 10.   | Directors, Executive Officers and Corporate Governance                                                       | 17
|Item 11.   | Executive Compensation.                                                                                      | 18
|Item 12.   | Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters.              | 18
|Item 13.   | Certain Relationships and Related Transactions, and Director Independence.                                   | 20
|Item 14.   | Principal Accounting Fees and Services.                                                                      | 20
|           |                                                                                                              |   
|PART IV    |                                                                                                              | 22
|Item 15.   | Exhibits, Financial Statement Schedules.                                                                     | 22
|           |                                                                                                              |   
|SIGNATURES | 23                                                                                                          









|Item 1. | Business
|------- | --------



History



Our company, FSP 50 South
Tenth Street Corp., which individually or together with its subsidiary, we refer to as the Company, we or our, is a Delaware corporation
formed to purchase, own and operate a twelve-story multi-tenant office and retail building containing approximately 498,768 square
feet of rentable space located in downtown Minneapolis, Minnesota, which we refer to as the Property. The Company operates in a
manner intended to qualify as a real estate investment trust, or REIT, for federal income tax purposes.



The Company was organized
initially in September 2006 by FSP Investments LLC (member, FINRA and SIPC), a wholly-owned subsidiary of Franklin Street Properties
Corp., which we refer to as Franklin Street (NYSE Amex: FSP). FSP Investments LLC acted as a real estate investment firm and broker/dealer
with respect to (a) the organization of the Company, (b) the acquisition of the Property by the Company and (c) the sale of equity
interests in the Company.



The Company purchased
the Property from an unaffiliated third party for $127,000,000 on November 8, 2006. The purchase price, which was determined by
arm’s-length negotiations, was financed entirely by a loan from Franklin Street collateralized by a first mortgage, which
we refer to as the Acquisition Mortgage Loan.



Franklin Street holds
the sole share of the Company’s common stock, $.01 par value per share, which we refer to as the Common Stock. Between November
2006 and January 2007, FSP Investments LLC completed the sale on a best efforts basis of 700 shares of preferred stock, $.01 par
value per share, which we refer to as the Preferred Stock. We sold the Preferred Stock for an aggregate consideration of $70,000,000
in a private placement offering to 627 “accredited investors” within the meaning of Regulation D under the Securities
Act of 1933. Between November 13, 2006 and January 9, 2007, the Company held six investor closings, at each of which shares of
Preferred Stock were sold and funds were received. Funds from each individual closing were used to repay a portion of the Acquisition
Mortgage Loan from Franklin Street and associated fees as well as other expenses payable to Franklin Street’s wholly-owned
subsidiary, FSP Investments LLC. On December 21, 2006, the Company obtained a permanent first mortgage loan in the original principal
amount of $76,200,000 from Bank of America, N.A., which we refer to as the Permanent Mortgage Loan. The Acquisition Mortgage Loan
was repaid in its entirety on December 26, 2006 from the proceeds of the sale of equity interests in the Company and from the proceeds
of the Permanent Mortgage Loan. Total interest and loan fees incurred on the Acquisition Mortgage Loan payable to Franklin Street
were approximately $4,961,000 in 2006. The use of proceeds received from the offering of Preferred Stock and the Permanent Mortgage
Loan and affiliates receiving payments therefrom are set forth in the table below:



|Type                                     |  | Affiliate paid                   | Amount          
|---------------------------------------- |  | -------------------------------- | ----------------
|Operating/Capital Reserve (1)            |  |                                  | $      8,209,000
|Organizational, Offering and             |  |                                  |                 
|Other Expenditures for the Company(2)(6) |  | FSP Investments LLC              | 725,000         
|Selling Commissions(3)                   |  | FSP Investments LLC              | 5,600,000       
|Equity Portion of the Purchase Price     |  |                                  |                 
|of the Property(4)                       |  | Franklin Street Properties Corp. | 50,800,000      
|Loan Fee Paid to Franklin Street (5)     |  | Franklin Street Properties Corp. | 4,025,000       
|Acquisition Fee(6)                       |  | FSP Investments LLC              | 350,000         
|Permanent Mortgage Loan fee & expenses   |  |                                  | 291,000         
|Total Uses of Proceeds                   |  |                                  | 70,000,000      
|Permanent Mortgage Loan                  |  |                                  | 76,200,000      
|                                         |  |                                  | $   146,200,000 



(1)	The Operating/Capital
Reserve proceeds were retained by the Company for operating and capital uses.

(2)	Organizational,
Offering and Other Expenditures were paid for various expenses, including legal, accounting, appraisal, engineering and organizational
expenses allocable to the offering, incurred in connection with the organization and syndication of the Company.

(3)	Selling
Commissions were paid to FSP Investments LLC, as Selling Agent.

(4)	The Purchase
Price of the Property was $127,000,000 and was financed by the Acquisition Mortgage Loan, which was repaid from proceeds of the
offering and the Permanent Mortgage Loan.

1





(5)	The Loan
Fee Paid to Franklin Street was a fee (or points) of $4,025,000 paid to Franklin Street to obtain the Acquisition Mortgage Loan
to purchase the Property. The Acquisition Mortgage Loan was in the original principal amount equal to the purchase price of the
Property, had a term of two years, and was prepayable at any time without premium or penalty and carried an interest rate equal
to the rate payable by Franklin Street on borrowings under its line of credit with its bank.

(6)	The Acquisition
Fee was paid for services in connection with identifying and acquiring the Property.



Transactions between the
Company and Franklin Street and/or its affiliates were entered into without the benefit of arm’s-length bargaining and involved
conflicts of interest. Although Franklin Street sponsors the syndication of other REITs similar to the Company and has in the past
acquired some of those REITs, Franklin Street is under no obligation to acquire or to offer to acquire the Company or the outstanding
shares of Preferred Stock, and any acquisition transaction would need to be approved by the Company’s stockholders and the
boards of directors of Franklin Street and the Company. Please see “Part III, Item 13. Certain Relationships and Related
Transactions, and Director Independence”.



Our Business



Our sole business is to
own and operate the Property and we do not intend to invest in or purchase any additional properties. We derive rental revenue
from income paid to us by the tenants of the Property. Property management services are provided by a third party.



FSP 50 South Tenth Street
LLC, a wholly-owned subsidiary of the Company, leases a portion of the Property from the Company and is the lessor for tenants
occupying the portion of the Property controlled by this master lease. This arrangement has no economic effect on the Company's
operations and exists only because the Company acquired the Property with a master lease in place.



The Property was completed
in 2001 and is leased to a diverse group of office and retail tenants with staggered lease expirations. The Property is located
directly across the street from the designated world headquarters of Target Corporation (NYSE: TGT), which we refer to as Target,
and is connected to a corporately-owned two-level Target retail store and sits above an approximately 850-stall, three-level parking
garage that is owned and managed by the City of Minneapolis.



The Property also has lower
level retail space and is part of a larger area that we refer to as the Project that covers a full city block in Minneapolis, Minnesota.
The Project is comprised of our Property, the Target retail store and the parking garage. The three owners of the Project, the
Company, Target and the City of Minneapolis, share expenses and responsibilities for maintenance of the Project under the terms
of a Reciprocal Easement and Operation Agreement (REOA), which is administered by Ryan Companies US, Inc., which we refer to as
Ryan. The three owners of the Project also share certain common areas and access to four skyway bridges that connect the Project
to other buildings, including Target’s world headquarters across the street, and the greater Minneapolis skyway system. Ryan
also serves as our property manager and is a tenant of ours at the Property. For the year ended December 31, 2010, total expenses
allocable to the three owners pursuant to the REOA were $0.7 million, of which $336,000 or 47.3% was allocated to us as common
area expenses. These common area expenses are typically recovered through tenant leases.



The Property has office
and retail space, which collectively was approximately 98.8% leased as of December 31, 2010. There is approximately 449,233 square
feet of rentable office space, which was approximately 100% leased as of December 31, 2010, and approximately 36,415 square feet
of rentable retail space, which was approximately 84.7% leased as of December 31, 2010 and approximately 13,120 square feet of
storage space, which was approximately 97.6% leased as of December 31, 2010. Target and Ryan currently occupy 10% or more of
the Property’s space. Oracle America, Inc., which we refer to as Oracle America, leases approximately 242,107 square feet
of space (approximately 50% of the Property’s rentable space) through March 2014. Oracle America subleases its space to Target
(approximately 215,838 square feet) and the balance (approximately 26,269 square feet) to another tenant. Oracle America was previously
known as Oracle USA, Inc., which we refer to as Oracle USA. Effective February 15, 2010, Oracle USA merged with and into Oracle
America, with Oracle America surviving the merger. In connection with this merger, Oracle USA assigned its lease at the Property
to Oracle America. Oracle America is and Oracle USA was a wholly-owned subsidiary of Oracle Corporation (NASDAQ: ORCL), which we
refer to as Oracle. Ryan leases approximately 86,381 square feet through July 2015, subject to Ryan’s right to terminate
the lease, commencing on December 31, 2011, prior to its scheduled expiration in 2015. In addition to its sublease, Target directly
leases approximately 43,506 square feet through June 2015 and approximately 1,024 square feet through October 2016. Including subleased
space, Target occupies approximately 54% of the Property's rentable space. Ryan occupies approximately 18% of the Property’s
rentable space. Except for Oracle America and Ryan, none of the Property’s additional office and retail tenants with direct
leases currently occupies 10% or more of the Property’s space.



2





For leases with 10%
or more of the rentable square feet of the property, the table below shows the estimated annual gross rent and annualized
gross rent per square foot, including estimated expense reimbursement for each lessee, and the percentage of gross annual
rental income for the Property. Renewal options for each of these leases are further discussed in “Part I, Item 2.
Properties” below. Except for Oracle America and Ryan, none of the Property’s additional office and retail
tenants with direct leases currently occupies 10% or more of the Property’s space.



|           |                 |  | Annualized   |  |       
|---------- | --------------- |  | ------------ |  | ------
|           |                 |  | Gross        |  | % of  
|           | Annual          |  | Rent         |  | Gross 
|           | Gross           |  | per          |  | Annual
|Tenant     | Rental          |  | Square Foot  |  | Rental
|Oracle USA | $     8,298,330 |  | $      32.98 |  | 51%   
|Ryan       | $     2,891,990 |  | $      32.38 |  | 18%   



Tenant leases at the Property
are generally structured so that each tenant pays a base rent amount for its premises and also pays a portion of the Property’s
operating costs as additional rent. The tenant’s portion of the Property’s operating costs is calculated by taking
the square footage of the tenant’s premises and dividing it by the total square footage of the Property. Operating costs
include, but are not limited to, costs associated with maintenance, repairs, real estate taxes, insurance, utilities and management
fees. In our capacity as the landlord, we are generally obligated, at our expense, to maintain and replace, if necessary, major
building systems and structural components of the Property, including exterior walls, roof and slab.



FSP Property Management
LLC, a wholly-owned subsidiary of Franklin Street, provides the Company with asset management and financial reporting services,
which include but are not limited to, selecting and supervising a local property management company and local leasing brokers,
approving lease transactions, managing debt compliance, evaluating performance of the asset, and recommending appropriate stockholder
distributions to the Board of Directors of the Company. The asset management agreement between the Company and FSP Property Management
LLC requires the Company to pay FSP Property Management LLC a monthly fee equal to one percent (1%) of the gross revenues of the
Property. The asset management agreement between the Company and FSP Property Management LLC may be terminated by the Company without
cause at any time, upon at least thirty (30) days written notice.



Ryan provides the Company
with local, on-site property management and building maintenance services and periodic financial, operating and budget reports
relating to the operation of the Property for review by FSP Property Management LLC. Ryan is a third-party service provider that
is not related to or affiliated with Franklin Street. The management agreement between the Company and Ryan requires the Company
to pay Ryan a monthly fee equal to three percent (3%) of the net operating receipts collected in the preceding month. The management
agreement between the Company and Ryan has an initial term that expires on December 31, 2012 and, unless terminated at that time,
automatically renews month-to-month thereafter. The management agreement may be terminated for cause at any time.



Investment Objectives



The Company’s objectives
are to (i) obtain cash available to pay dividends through rental receipts from operations of the Property, (ii) have that cash
increase over time as a result of rental rate step increases in existing leases, (iii) have our rental revenue potentially increase
over time if rental rates increase for new leases, subject to the qualification that approximately 52% and 33% of the currently
leased rentable space at the Property expires in 2014 and 2015, respectively, which limits the amount of space for which new leases
could be executed until that time, (iv) provide increased equity in the Property as a result of appreciation in market value, and
(v) preserve and protect the capital invested by the holders of our Preferred Stock. We cannot be sure of meeting our objectives.



Our policy is not to make
loans to other persons, not to invest in the securities of other issuers for the purpose of exercising control, not to underwrite
the securities of other issuers, not to offer securities in exchange for property and not to purchase or otherwise reacquire our
securities. These policies may be changed by our directors without a vote of the holders of our Preferred Stock.



3





We have issued 700
shares of Preferred Stock in the offering described above. The Company’s Amended and Restated Certificate of Incorporation,
or charter, authorizes the Company to issue up to 1,540 shares of Preferred Stock. In the event that the Company elects, in its
sole and absolute discretion, to reduce the principal amount of the Permanent Mortgage Loan, the Company will have the right, without
the consent of any holder of shares of our Preferred Stock, to issue up to 840 additional shares of Preferred Stock. We expect
that any such issuance would be in an offering exempt from registration under the Securities Act. No additional shares of Preferred
Stock are authorized by our charter, and authorization of any increase in the number of authorized shares or the creation of any
new series or class of stock would require the affirmative vote of the holders of 66.67% of the outstanding shares of Preferred
Stock.

We intend to dispose of
the Property at such time that our directors determine that we have achieved our investment objectives. We do not intend to reinvest
the proceeds and would distribute cash proceeds to shareholders following such disposition. We also do not intend to list our shares
of Preferred Stock on an exchange and therefore do not expect any trading market to develop in such shares.



Except for the Permanent
Mortgage Loan, which matures on January 1, 2012, we do not intend to borrow any money but have the right to obtain a line of credit
as described below. There can be no assurance that the Company will be able to sell or refinance the Property upon the maturity
of the Permanent Mortgage Loan or that the proceeds received from such sale or refinancing, or cash raised from the issuance of
up to an additional 840 shares of Preferred Stock or the use of our line of credit will be sufficient to repay the Permanent Mortgage
Loan at that time. The Board of Directors of the Company has not yet determined whether it will issue additional shares of Preferred
Stock or refinance or sell the Property in connection with the maturity of the Permanent Mortgage Loan, and, because we cannot
predict the state of the capital markets during the remainder of 2011, we cannot predict how we will retire the Permanent Mortgage
Loan.



Permanent Mortgage Loan



The Property is subject
to the Permanent Mortgage Loan with Bank of America, N.A. The Permanent Mortgage Loan closed on December 21, 2006 and is secured
by, among other items, a first mortgage lien on the Property. The principal amount of the Permanent Mortgage Loan is $76,200,000
and interest is fixed at 5.287% per annum. The Permanent Mortgage Loan matures on January 1, 2012. The Company is obligated to
make monthly payments of interest only until the maturity date, at which time the principal amount of the Permanent Mortgage Loan,
together with any accrued but unpaid interest, is due and payable in full. The Company may prepay (in full but not in part) the
Permanent Mortgage Loan upon payment of an amount equal to the greater of 1% of the principal balance outstanding or the product
of a yield maintenance calculation. The yield maintenance formula represents the difference between the interest rate on the Permanent
Mortgage Loan and that of a comparable U.S. Treasury Security of similar maturity. Additionally, the Company may prepay (in full
but not in part) the Permanent Mortgage Loan without penalty at any time during the final six months of the Permanent Mortgage
Loan. The Permanent Mortgage Loan is nonrecourse to the Company.



The documentation evidencing
and securing the Permanent Mortgage Loan, which we refer to as the Loan Agreement, includes restrictions on property liens and
requires compliance with various financial covenants. Financial covenants include the requirement that the Company deposit all
rents or other revenue from the Property to a lockbox account with the lender, which so long as there is no default, is immediately
available to us, and to provide the lender with periodic reporting. The Loan Agreement also includes restrictions on the Company’s
ability to incur additional debt without consent of the lender. The Company was in compliance with the Permanent Mortgage Loan
covenants as of December 31, 2010.



Revolving Line of Credit



While a line of credit
is not expected to be needed, the Company may, without the consent of any holder of shares of our Preferred Stock, obtain a revolving
line of credit of up to $76,200,000 on commercially reasonable terms to be used for capital improvements, operating expenses, working
capital requirements or to refinance the Company’s debt and fund other Company purposes, if needed. However, pursuant to
the Permanent Mortgage Loan, we need the consent of Bank of America, N.A. to use the line of credit. As of February 28, 2011, the
Company had neither sought nor obtained a revolving line of credit.



4





Competition



The Property is
located in the downtown area of Minneapolis, Minnesota. The Property may encounter substantial competition from the other
office buildings which are or may become available in the general area in which the Property is located and which may be
priced at rental levels lower than those for space in the Property or which may otherwise be more attractive to tenants. In
order to maintain or increase rental revenues following the expiration of our leases, the Property must be competitive, in
regard to cost and amenities, with other buildings of similar use near our location. Some of our competitors may have
significantly more resources than we do and may be able to offer more attractive rental rates or services. On the other hand,
some of our competitors may be smaller or have lower fixed overhead costs, less cash or other resources that make them
willing or able to accept lower rents in order to maintain a certain occupancy level. If there is not currently significant
existing property competition, our competitors may decide to enter the market and build new buildings to compete with our
Property. Our competition is not only with other developers, but also with property users who choose to own their building.
In addition, larger market forces beyond our control, such as general economic conditions,  may increase
competition among landlords for quality tenants and individual decisions beyond our control. Subject to possible extension
options, approximately 52% of the rentable space at the Property expires in 2014 and approximately 33% of the rentable space
at the Property expires in 2015. Ryan has the right to terminate its lease, commencing on December 31, 2011, prior to its
scheduled expiration in 2015. We cannot predict which competitive factors will be relevant to prospective tenants or
our Property’s competitive position in the marketplace when those leases expire.



Management believes that
the position of the Property within Minneapolis’ office and retail markets is strong. In order to further improve the Property’s
position in Minneapolis’ office and retail markets, throughout 2010, management evaluated the Property’s operations
for both greater efficiency and for more active and proactive sustainability practices. The Property is Energy Star® certified
and, on November 1, 2010, earned LEED® Gold certification from the U.S. Green Building Council in the Leadership in Energy
and Environmental Design for Existing Buildings: Operations and Maintenance.



Employees



We had no employees as
of December 31, 2010.



Available Information



We
are subject to the informational requirements of the Securities Exchange Act of 1934, and, in accordance therewith, we file reports
and other information with the Securities and Exchange Commission (SEC). This Annual Report on Form 10-K and other reports
and other information we file can be inspected and copied at the SEC Public Reference Room at 100 F Street, N.E., Washington, D.C.
20549 on official business days during the hours of 10:00 am to 3:00 pm. Such reports, proxy and information statements, if any,
and other information about issuers that file electronically with the SEC may also be obtained from the web site that the SEC maintains
at http://www.sec.gov. Further information about the operation of the Public Reference Room may be obtained by calling the SEC
at 1-800-SEC-0330.



We will make available
and voluntarily provide, free of charge upon written request at the address on the cover of this Annual Report on Form 10-K, a
copy of our Annual Report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports
filed or furnished pursuant to Section 13(a) of the Exchange Act as soon as reasonably practicable after we electronically file
such material with, or furnish such material to, the SEC. We do not maintain a website.



|Item 1A. | Risk Factors
|-------- | ------------



Not applicable.



|Item 1B. | Unresolved Staff Comments
|-------- | -------------------------



Not applicable.

5







|Item 2. | Properties
|------- | ----------



Set forth below is information
regarding the Property as of December 31, 2010:



|                       |          |             | Percent     |            |                          
|---------------------- | -------- | ----------- | ----------- | ---------- | -------------------------
|                       | Date of  | Approx.     | Leased as   | Number     |                          
|Property Location      | Purchase | Square Feet | of 12/31/10 | of Tenants | Name of Major Tenants (1)
|                       |          |             |             |            |                          
|50 South Tenth Street  | 11/08/06 | 498,768     | 98.8%       | 28         | Oracle America (2)       
|Minneapolis , MN 55403 |          |             |             |            | Ryan Companies US, Inc.  



1.	Excludes
subtenants.

2.	Oracle
America leases approximately 242,107 square feet of space (approximately 50% of the Property’s rentable space) through March
2014. Oracle America subleases most of its space to Target (approximately 215,838 square feet) and the balance (approximately 26,269
square feet) to another tenant.



The
Property was completed in 2001 and is leased to a diverse group of office and retail tenants with staggered lease expirations.
The Property is located directly across the street from the world headquarters of Target, is connected to a corporately-owned two-level
Target retail store and sits above an approximately 850-stall, three-level underground parking garage that is owned and managed
by the City of Minneapolis.The Property also has lower level retail space and is part of a larger development that we refer
to as the Project that covers a full city block in Minneapolis, Minnesota. The Project is comprised of our Property, the Target
retail store and the parking garage. The three owners of the Project, our Company, Target and the City of Minneapolis, share expenses
and responsibilities for maintenance of the Project under the terms of a Reciprocal Easement and Operation Agreement (REOA), which
is administered by Ryan. The three owners of the Project also share certain common areas and access to four skyway bridges that
connect the Project to other buildings, including Target’s world headquarters across the street, and the greater Minneapolis
skyway system.



We
acquired the Property on November 8, 2006. In the opinion of our management, the Property is adequately covered by insurance. The
Property is currently encumbered by the Permanent Mortgage Loan described above in “Item 1. Business–Permanent Mortgage Loan.” Other than normal tenant improvements or replacements of equipment in the ordinary course of ongoing
operations, there are no present plans for the improvement or development of any portion of the Property. Below is certain information
with respect to the Property’s significant tenants and leases.



Tenants



The Property has
office and retail space, which collectively was approximately 98.8% leased as of December 31, 2010. There is approximately
449,233 square feet of rentable office space, which was approximately 100% leased  as of December 31, 2010, and approximately
36,415 square feet of rentable retail space, which was approximately 84.7% leased as of December 31, 2010 and approximately
13,120 square feet of storage space, which was approximately 97.6% leased as of December 31, 2010. Target and Ryan
currently occupy 10% or more of the Property’s space. Oracle USA, Inc., which we refer to as Oracle USA, leases
approximately 250,115 square feet of space (approximately 50% of the Property’s rentable space) through March 2014.
Oracle USA subleases most of its space to Target (approximately 223,846 square feet) and the balance (approximately 26,269
square feet) to another tenant. Oracle USA is a subsidiary of Oracle Corporation (NASDAQ: ORCL), which we refer to as Oracle.
Ryan leases approximately 86,381 square feet through July 2015, subject to Ryan’s right to terminate the lease,
beginning on December 31, 2011, prior to its scheduled expiration. Target directly leases approximately 43,506 square feet
through June 2015 and approximately 1,024 square feet through October 2016. Including subleased space, Target occupies
approximately 54% of the Property's rentable space. Ryan occupies approximately 18% of the Property’s rentable space.
Except for Oracle USA and Ryan, none of the Property’s additional office and retail tenants with direct
leases currently occupies 10% or more of the Property’s space.



6





Leases



Tenant leases at the Property
are generally structured so that each tenant pays a base rent amount for its premises and also pays a portion of the Property’s
operating costs as additional rent. The tenant’s portion of the Property’s operating costs is calculated by taking
the square footage of the tenant’s premises and dividing it by the total square footage of the Property. Operating costs
include, but are not limited to, costs associated with maintenance, repairs, real estate taxes, insurance, utilities and management
fees. In our capacity as the landlord, we are generally obligated, at our expense, to maintain and replace, if necessary, major
building systems and structural components of the Property, including exterior walls, roof and slab. Abstract of material leases
are noted below:



Oracle America

Oracle America leases approximately
242,107 square feet of rentable space (approximately 50% of the Property’s space). The lease expires on March 31, 2014 and
contains two five-year extension options with base rent equal to the greater of (i) $18.85 per rentable square foot or (ii) the
market rent for such extension term. In order to exercise either extension option, Oracle America must provide the Company with
not less than nine months prior written notice. The lease with Oracle America also contains a continuing right of first refusal
in favor of Oracle America on all other office rental space at the Property. Oracle America’s lease does not contain any
other rights of first offer, purchase, expansion or termination at the Property. Oracle America subleases most of its space to
Target (approximately 215,838 square feet) and the balance (approximately 26,269 square feet) to another tenant.



Ryan

Ryan leases a total of
approximately 86,381 rentable square feet (approximately 18% of the Property's space) pursuant to a lease that expires on July
31, 2015. The lease contains a termination right in favor of Ryan that permits Ryan to terminate the lease effective either (i)
as of December 31, 2011 or (ii) on the last day of any month after December 31, 2011. In order to exercise the termination right,
Ryan must provide the Company with written notice of its intention to terminate not less than three months prior to the intended
termination date. Ryan's lease does not contain any other rights of first offer, purchase, expansion or termination at the Property.



Additional Operating Data



Additional information
regarding the amount of the Property’s annual real estate taxes and insurance can be found in the Statements of Operations
that are included with this Form 10-K. Additional information regarding the Property’s Federal tax basis, rate, method and
life claimed for purposes of depreciation can be found in the Notes to Consolidated Financial Statements that are included with
this Annual Report on Form 10-K.



|Item 3. | Legal Proceedings
|------- | -----------------



There are no material legal
proceedings to which the Company is a party. The Company from time to time may be involved in lawsuits including, but not limited
to, lawsuits relating to the real property it owns for liability for slips and falls, damage to automobiles in the parking garage,
minor theft or similar matters. The Company expects that most of these suits will be covered by insurance, subject to customary
deductions. In addition, in the ordinary course of business, the Company may become involved in litigation to collect rents or
other income due to it from tenants.



|Item 4. | Removed and Reserved
|------- | --------------------





7





PART II



|Item 5. | Market For Registrant’s Common Equity,  Related Stockholder Matters and Issuer Purchases
    of Equity Securities
|------- | -----------------------------------------------------------------------------------------------------------------



There is no established
public trading market for the Company’s Common Stock or Preferred Stock.



As of February 28, 2011,
Franklin Street was the sole holder of record of the Common Stock and there were 634holders
of record of the Preferred Stock. This computation is based upon the number of record holders reflected in our corporate records.
The final sale of Preferred Stock occurred on January 9, 2007 and following that date no further distributions have been or will
be declared on the Common Stock. The last Common Stock dividend was declared on December 27, 2006 and was paid in December 2006.



Set forth below are the
distributions made to Preferred Stockholders in respect of each quarter from the last two fiscal years. Distributions are determined
based on the Company’s Board of Directors’ review of cash available for distribution and distribution requirements
necessary for the Company to continue to qualify as a real estate investment trust. We cannot guarantee the future payment of dividends
or the amount of any such dividends. See the Notes to Consolidated Financial Statements that are included with this Annual Report
on Form 10-K for additional information.



|                   |  | Distributions          
|------------------ |  | -----------------------
|                   |  | paid to                
|Quarter            |  | Preferred              
|Ended              |  | Stockholders           
|                   |  |                        
|March 31, 2009     |  | $         1,225,000    
|June 30, 2009      |  | 1,225,000              
|September 30, 2009 |  | 1,225,000              
|December 31, 2009  |  | 1,225,000              
|                   |  |                        
|March 31, 2010     |  | $        
    1,225,000
|June 30, 2010      |  | 1,225,000              
|September 30, 2010 |  | 1,225,000              
|December 31, 2010  |  | 1,225,000              



The following schedule
summarizes tax components of the distributions paid for the years ended December 31:



|(dollars in thousands) |  | 2010      |       | 2009
|---------------------- |  | --------- | ----- | ----
|                       |  | Preferred |       | %   
|Ordinary income        |  | $         | 1,042 |     
|Return of Capital      |  |           | 3,858 |     
|                       |  |           |       |     
|Total                  |  | $         | 4,900 |     



The Company does not have
an equity compensation plan or any outstanding stock options or other securities convertible into the Company’s Common Stock.



|Item 6. | Selected Financial Data
|------- | -----------------------



Not applicable.

8







|Item 7. | Management’s Discussion and Analysis of Financial Condition and Results of Operations
|------- | -------------------------------------------------------------------------------------



The following discussion
should be read in conjunction with the financial statements and notes thereto appearing elsewhere in this report. Historical results
and percentage relationships set forth in the consolidated financial statements, including trends which might appear, should not
be taken as necessarily indicative of future operations. The following discussion and other parts of this Annual Report on Form
10-K may also contain forward-looking statements based on current judgments and current knowledge of management, which are subject
to certain risks, trends and uncertainties that could cause actual results to differ materially from those indicated in such forward
looking statements. Accordingly, readers are cautioned not to place undue reliance on forward-looking statements. Investors are
cautioned that our forward-looking statements involve risks and uncertainty, including without limitation, economic conditions
in United States and in the market where we own the Property, continued disruptions in the debt markets, risks of a lessening of
demand for the type of real estate owned by us, changes in government regulations, and expenditures that cannot be anticipated
such as utility rate and usage increases, unanticipated repairs, additional staffing, insurance increases and real estate tax valuation
reassessments. Although we believe the expectations reflected in the forward-looking statements are reasonable, we cannot guarantee
future results, levels of activity, performance or achievements. We may not update any of the forward-looking statements after
the date this Annual Report on Form 10-K is filed to conform them to actual results or to changes in our expectations that occur
after such date, other than as required by law.



Overview



FSP 50 South Tenth Street
Corp., which we refer to as the Company, is a Delaware corporation formed to purchase, own and operate a twelve-story multi-tenant
office and retail building containing approximately 498,768 square feet of rentable space located in downtown Minneapolis, Minnesota,
which we refer to as the Property.



Franklin Street Properties
Corp., which we refer to as Franklin Street, is the sole holder of our one share of common stock, $.01 par value per share, which
we refer to as the Common Stock, that is issued and outstanding. Between November 2006 and January 2007, FSP Investments LLC (member
FINRA and SIPC), a wholly-owned subsidiary of Franklin Street, completed the sale on a best efforts basis of 700 shares of our
preferred stock, $.01 par value per share, which we refer to as the Preferred Stock. FSP Investments LLC sold the Preferred Stock
in a private placement offering to “accredited investors” within the meaning of Regulation D under the Securities Act
of 1933. Since the completion of the placement of the Preferred Stock in January 2007, Franklin Street has not been entitled to
share in any earnings or dividend related to the Common Stock.



We operate in one business
segment, which is real estate operations, and own a single property. Our real estate operations involve real estate rental operations,
leasing services and property management services. The main factor that affects our real estate operations is the broad economic
market conditions in the United States and, more specifically, the economic conditions in Minneapolis, Minnesota. These market
conditions affect the occupancy levels and the rent levels on both a national and local level. We have no influence on national
or local market conditions.



Trends and Uncertainties



Economic Conditions



The economy in
the United States is continuing to experience a period of limited economic growth, including historically high levels
of unemployment, the failure and near failure of a number of large financial institutions, reduced liquidity and
increased credit risk premiums for a number of market participants. Economic conditions may be affected by numerous factors,
including but not limited to, inflation and employment levels, energy prices, recessionary concerns, changes in currency
exchange rates, the availability of debt and interest rate fluctuations. Management does not believe that the current state
of the U.S. economy has negatively impacted our business at this time. However, management does believe that the current
state of the U.S. economy has negatively impacted real estate values, occupancy levels and property income levels in the
United States and, as a consequence, is closely monitoring the situation. For the three months ended December 31, 2010, the
Class A office market in downtown Minneapolis experienced positive absorbtion for the fourth straight quarter. In addition,
for the three months ended December 31, 2010, we believe that vacancy rates decreased slightly and that rental rates were
flat compared to the third quarter for office and retail buildings in downtown Minneapolis. These local and national trends
may continue, worsen or improve in the future. At this time, we cannot predict the extent or duration of any negative impact
that the current state of the U.S. economy will have on our business.

9





Real Estate Operations



We own and operate a twelve-story
multi-tenant office and retail building containing approximately 498,768 of rentable square feet located in downtown Minneapolis,
Minnesota. The Property was completed in 2001 and is leased to a diverse group of office and retail tenants with staggered lease
expirations. The Property is located directly across the street from the designated world headquarters of Target Corporation (NYSE:TGT),
which we refer to as Target, and is connected to a corporately-owned two-level Target retail store and sits above an approximately
850-stall, three-level parking garage that is owned and managed by the City of Minneapolis. The Property also has lower level retail
space and is part of a larger development that we refer to as the Project that covers a full city block in Minneapolis, Minnesota.
The Project is comprised of our Property, the Target retail store and the parking garage. The three owners of the Project, our
Company, Target and the City of Minneapolis, share expenses and responsibilities for maintenance of the Project under the terms
of a Reciprocal Easement and Operation Agreement (REOA), which is administered by Ryan. The three owners of the Project also share
certain common areas and access to four skyway bridges that connect the Project to other buildings, including Target’s world
headquarters across the street, and the greater Minneapolis skyway system.



The Property has
office and retail space, which collectively was approximately 98.8% leased as of December 31, 2010. There is approximately
449,233 square feet of rentable office space, which was approximately 100% leased  as of December 31, 2010 and approximately
36,415 square feet of rentable retail space, which was approximately 84.7% leased as of December 31, 2010 and approximately
13,120 square feet of storage space, which was approximately 97.6% leased as of December 31, 2010. Target and Ryan
currently occupy 10% or more of the Property’s space. Oracle America, Inc., which we refer to as Oracle America, leases
approximately 242,107 square feet of space (approximately 50% of the Property’s rentable space) through March 2014.
Oracle America subleases its space to Target (approximately 215,838 square feet) and the balance (approximately 26,269 square
feet) to another tenant. Oracle America was previously known as Oracle USA, Inc., which we refer to as Oracle USA. Effective
February 15, 2010, Oracle USA merged with and into Oracle America, with Oracle America surviving the merger. In connection
with this merger, Oracle USA assigned its lease at the Property to Oracle America. Oracle America is and Oracle USA was a
wholly-owned subsidiary of Oracle Corporation (NASDAQ: ORCL), which we refer to as Oracle. Ryan leases approximately 86,381
square feet through July 2015, subject to Ryan’s right to terminate the lease, beginning on December 31, 2011, prior to
its scheduled expiration. Target directly leases approximately 43,506 square feet through June 2015 and approximately 1,024
square feet through October 2016. Including subleased space, Target occupies approximately 54% of the Property's rentable
space. Ryan occupies approximately 18% of the Property’s rentable space. Except for Oracle America and Ryan, none of
the Property’s additional office and retail tenants with direct leases currently occupies 10% or more of the
Property’s space.



During the fourth quarter
of 2010, management was successful in causing the Company to enter into new retail leases and/or to renew existing retail leases
totaling approximately 12,000 square feet. For the remainder of 2011, that leaves only approximately 7,000 square feet of leased
space that is scheduled to expire. Management is already in discussions with the applicable tenants regarding this space and is
optimistic regarding their probability for renewal. Management, through its local representatives, continues to monitor performance
and needs of some of the retail tenants and is working with some of the smaller tenants to identify strategies for improving their
visibility in an ongoing effort to enhance the overall performance of the Property’s retail tenants.



Management believes that
the position of the Property within Minneapolis’ office and retail markets is strong. In order to further improve the Property’s
position in Minneapolis’ office and retail markets, throughout 2010, management evaluated the Property’s operations
for both greater efficiency and for more active and proactive sustainability practices. The Property is Energy Star® certified
and, on November 1, 2010, earned LEED® Gold certification from the U.S. Green Building Council in the Leadership in Energy
and Environmental Design for Existing Buildings: Operations and Maintenance.



It is difficult for management
to predict what will happen to occupancy or rents after the expiration or earlier termination of existing leases at our Property
because the need for space and the price tenants are willing to pay are tied to both the local economy and to the larger trends
in the national economy, such as job growth, interest rates, the availability of credit and corporate earnings, which in turn are
tied to even larger macroeconomic and political factors, such as recessionary concerns, volatility in energy pricing and the risk
of terrorism. In addition to the difficulty of predicting macroeconomic factors, it is difficult to predict how our local market
or tenants will suffer or benefit from changes in the larger economy. In addition, because the Property is in a single geographical
market, these macroeconomic trends may have a different effect on the Property and on its tenants, many of which operate on a national
level. Although we cannot predict how long it would take to lease vacant space at the Property or what the terms and conditions
of any new leases would be, we would expect to sign new leases at current market rates which may be below the expiring rates.



10





Given the current economic
downturn, the potential for any of our tenants to default on its lease or to seek the protection of bankruptcy laws has increased.
If any of our tenants defaults on its lease, we may experience delays in enforcing our rights as a landlord and may incur substantial
costs in protecting our investment. In addition, at any time, a tenant may seek the protection of bankruptcy laws, which could
result in the rejection and termination of such tenant’s lease and thereby cause a reduction in cash available for distribution
to our stockholders. Bankruptcy or a material adverse change in the financial condition of a material tenant would likely have
a material adverse effect on our results of operations.



Critical Accounting Policies and Estimates



We have certain critical
accounting policies that are subject to judgments and estimates by our management and uncertainties of outcome that affect the
application of these policies. We base our estimates on historical experience and on various other assumptions we believe to be
reasonable under the circumstances. On an ongoing basis, we evaluate our estimates. In the event estimates or assumptions prove
to be different from actual results, adjustments are made in subsequent periods to reflect more current information. The accounting
policies that we believe are most critical to the understanding of our financial position and results of operations, and that require
significant management estimates and judgments, are discussed below.



Critical accounting policies
are those that have the most impact on the reporting of our financial condition and results of operations and those requiring significant
judgments and estimates. We believe that our judgments and estimates are consistently applied and produce financial information
that fairly presents our results of operations. These policies affect our:



|· |  | recognition
of rental income and depreciation and amortization expense; and
|- |  | ---------------------------------------------------------------------------

|· |  | assessment
of the carrying values and impairments of long-lived assets.
|- |  | -----------------------------------------------------------------------



Depreciation and Amortization



We compute depreciation
expense using the straight-line method over estimated useful lives of up to 39 years for the building and improvements, and up
to 15 years for personal property. The allocated cost of land is not depreciated. The value of above or below-market leases are
amortized over the remaining non-cancelable periods of the lease as an adjustment to rental income. The value of in-place leases,
exclusive of the value of above-market and below-market in-place leases, is also amortized over the remaining non-cancelable periods
of the respective leases. If a lease is terminated prior to its stated expiration, all unamortized amounts relating to that lease
would be written off. Inappropriate allocation of acquisition costs, or incorrect estimates of useful lives, could result in depreciation
and amortization expenses which do not appropriately reflect the allocation of our capital expenditures over future periods, as
is required by generally accepted accounting principles.



Impairment



We periodically evaluate
the Property for impairment indicators. These indicators may include declining tenant occupancy, weak or declining tenant profitability,
cash flow or liquidity, our decision to dispose of an asset before the end of its estimated useful life or legislative, economic
or market changes that permanently reduce the value of our investment. If indicators of impairment are present, we evaluate the
carrying value of the Property by comparing it to its expected future undiscounted cash flows. If the sum of these expected future
cash flows is less than the carrying value, we reduce the net carrying value of the Property to the present value of these expected
future cash flows. This analysis requires us to judge whether indicators of impairment exist and to estimate likely future cash
flows. If we misjudge or estimate incorrectly or if future tenant profitability, market or industry factors differ from our expectations,
we may record an impairment charge which is inappropriate or fail to record a charge when we should have done so, or the amount
of such charges may be inaccurate.



Lease Classification



Each time we enter a new
lease or materially modify an existing lease we evaluate whether it is appropriately classified as a capital lease or as an operating
lease. The classification of a lease as capital or operating affects the carrying value of a property, as well as our recognition
of rental payments as revenue. These evaluations require us to make estimates of, among other things, the remaining useful life
and market value of a property, discount rates and future cash flows. Incorrect assumptions or estimates may result in misclassification
of our leases.



11





Results of Operations



Comparison of the year
ended December 31, 2010 to the year ended December 31, 2009



Revenue



Total
revenue decreased $0.2 million to $16.0 million for the year ended December 31, 2010, as compared to $16.2 million for the year
ended December 31, 2009.This decrease was primarily due to a decrease in recovery of expenses of approximately $0.2 million.
The majority of the operating expenses, real estate taxes and insurance expenses represent amounts recoverable by the Company.



Expenses



Total expenses decreased
approximately $0.2 million to $14.9 million for the year ended December 31, 2010, as compared to $15.1 million for the year ended
December 31, 2009. The decrease was primarily attributable to a $0.2 million decrease in real estate taxes.



Liquidity and Capital
Resources



Cash and cash equivalents
decreased approximately $1.0 million to $8.9 million at December 31, 2010, as compared to $9.9 million for the year ended December
31, 2009. Cash provided by operating activities was $4.3 million and was offset by $0.4 million used for investing activities and
$4.9 million used for financing activities.



As
of December 31, 2010, we have a loan agreement, which we refer to as the Loan, outstanding with Bank
of America, N.A. in the amount of $76.2 million. The Loan is secured by the Property and matures on January
1, 2012. We anticipate that we will replace or refinance the Loan on or before its maturity date. However,
there can be no assurance that we will be able to replace or refinance the Loan on favorable terms, or
at all.

Management believes that
existing cash and cash equivalents as of December 31, 2010 of $8.9 million and cash anticipated to be generated internally by operations
will be sufficient to meet working capital requirements, distributions and anticipated capital expenditures for at least the next
12 months.



Operating Activities



The cash provided by operating
activities of $4.3 million for the year ended December 31, 2010 was primarily attributable to net income of approximately $1.1
million plus non-cash items of $3.7 million, consisting primarily of depreciation and amortization, and was partially offset by
uses arising from other current accounts of approximately $0.3 million and payments in deferred leasing costs of $0.2 million.



Investing Activities



The cash used for investing
activities for the year ended December 31, 2010 of approximately $0.4 million was attributable to the purchase of real estate assets.



Financing Activities



The cash used for financing
activities of approximately $4.9 million for the year ended December 31, 2010 was primarily attributable to distributions to stockholders.



Sources and Uses of
Funds



Our principal demands on
liquidity are cash for operations, interest on debt payments and distributions to equity holders. As of December 31, 2010, we had
approximately $1.7 million in accrued liabilities and $76.2 million in long-term debt. In the near term, liquidity is generated
by cash from operations.



Cash held in escrow



We also have cash held
in escrow of $1.4 million as of December 31, 2010. We are required under our loan documents to make monthly deposits into a pledge
account for real estate taxes, which is used to make periodic payments of those taxes. Increases and decreases to the cash held
in escrow are a result of the timing of monthly deposits and payment of periodic real estate tax assessments.

12





Secured Debt



We have a loan agreement,
which we refer to as the Loan, outstanding with Bank of America, N.A. in the amount of $76,200,000. Loan payments are interest-only
until the Loan matures and bear interest at the fixed rate of 5.287% per annum. The Loan is secured by the Property. The Loan was
entered into on December 21, 2006 and matures on January 1, 2012, with the entire principal balance due on that date. Interest
expense for the years ended December 31, 2010 and 2009 was $4,085,000 and $4,086,000, respectively.



The Loan agreement includes
restrictions on property liens and requires compliance with various financial covenants. Financial covenants include the requirement
that we deposit all rents or other revenue from the Property to a lockbox account with the lender and provide periodic reporting.
The Loan agreement contains certain restrictions on our ability to incur debt. We were in compliance with the loan covenants as
of December 31, 2010 and 2009.



Contingencies



We may be subject to various
legal proceedings and claims that arise in the ordinary course of our business. Although occasional adverse decisions or settlements
may occur, we believe that the final disposition of such matters will not have a material adverse effect on our financial position
or results of operations.



Related Party Transactions



We have in the past engaged
in and currently engage in transactions with a related party, Franklin Street and its subsidiaries FSP Investments LLC and FSP
Property Management LLC, which we collectively refer to as FSP. We expect to continue to have related party transactions with FSP
in the form of management fees paid to FSP to manage the Company on behalf of our stockholders. FSP Property Management LLC currently
provides the Company with asset management and financial reporting services. The asset management agreement between the Company
and FSP Property Management LLC requires the Company to pay FSP Property Management LLC a monthly fee equal to one percent (1%)
of the gross revenues of the Property. The asset management agreement between the Company and FSP Property Management LLC may be
terminated by either party without cause at any time, upon at least thirty (30) days written notice, effective at the end of the
notice period. For the years ended December 31, 2010 and 2009, management fees paid were $161,000 and $162,000, respectively.



Franklin Street is the
sole holder of the Company’s one share of Common Stock that is issued and outstanding. Subsequent to the completion of the
private placement of the Preferred Stock in January 2007, Franklin Street has not been entitled to share in any earnings or any
dividend as a result of its ownership of the Common Stock of the Company.



13





Rental Income Commitments



Our commercial real estate
operations consist of the leasing of the Property. Approximate future minimum rental income under non-cancelable operating leases
as of December 31, 2010 is as follows:



|Year Ending  |  | Amount            
|------------ |  | ------------------
|December 31, |  | (in thousands)    
|2011         |  | $            8,957
|2012         |  | 7,490             
|2013         |  | 7,421             
|2014         |  | 3,580             
|2015         |  | 1,547             
|Thereafter   |  | 2,441             
|             |  |                   
|             |  | $           31,436



Off-Balance Sheet Arrangements



The Company is not party
to any off-balance sheet arrangements other than property management commitments. The Company is a party to a management agreement
with Ryan, an unaffiliated third party management company that is a tenant of the Property, to provide property management services,
and is party to an asset management agreement with an affiliate, FSP Property Management LLC, to provide asset management and financial
reporting services. The management agreement between the Company and Ryan requires the Company to pay Ryan a monthly fee equal
to three percent (3%) of the net operating receipts collected in the preceding month. The management agreement between the Company
and Ryan has an initial term that expires on December 31, 2012 and, unless terminated at that time, automatically renews month-to-month
thereafter. The management agreement with Ryan may be terminated by the Company for cause at any time. The agreement with FSP Property
Management LLC may be terminated by either party without cause at any time, upon at least thirty (30) days written notice. The
asset management agreement between the Company and FSP Property Management LLC requires the Company to pay FSP Property Management
LLC a monthly fee equal to one percent (1%) of the gross revenues of the Property.



|Item 7A. | Quantitative and Qualitative Disclosure About Market Risk
|-------- | ---------------------------------------------------------



Not applicable.



|Item 8. | Financial Statements and Supplementary Data
|------- | -------------------------------------------



The information required by this item is included
elsewhere herein and incorporated herein by reference. Reference is made to the Index to Consolidated Financial Statements in Item
15 of Part IV.



|Item 9. | Changes in and Disagreements With Accountants on Accounting and Financial Disclosure
|------- | ------------------------------------------------------------------------------------



Not applicable.



14







|Item 9A. | Controls and Procedures
|-------- | -----------------------



Disclosure Controls and Procedures



Our management, with the
participation of our principal executive officer and principal financial officer, evaluated the effectiveness of our disclosure
controls and procedures as of December 31, 2010. The term “disclosure controls and procedures,” as defined in Rules
13a-15(e) and 15d-15(e) under the Securities Exchange Act of 1934, or the Exchange Act, means controls and other procedures of
a company that are designed to ensure that information required to be disclosed by a company in the reports that it files or submits
under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the SEC's rules and
forms. Disclosure controls and procedures include, without limitation, controls and procedures designed to ensure that information
required to be disclosed by a company in the reports that it files or submits under the Exchange Act is accumulated and communicated
to the company’s management, including its principal executive and principal financial officers, as appropriate to allow
timely decisions regarding required disclosure. Management recognizes that any controls and procedures, no matter how well designed
and operated, can provide only reasonable assurance of achieving their objectives and management necessarily applies its judgment
in evaluating the cost-benefit relationship of possible controls and procedures. Based on the evaluation of our disclosure controls
and procedures as of December 31, 2010, our principal executive officer and principal financial officer concluded that, as of such
date, our disclosure controls and procedures were effective at the reasonable assurance level.



Management’s Annual Report on Internal
Control Over Financial Reporting



The management of the Company
is responsible for establishing and maintaining adequate internal control over financial reporting. Internal control over financial
reporting is defined in Rule 13a-15(f) or 15d-15(f) promulgated under the Securities Exchange Act of 1934 as a process designed
by, or under the supervision of, the Company’s principal executive and principal financial officer and effected by the Company’s
board of directors, management and other personnel, to provide reasonable assurance regarding the reliability of financial reporting
and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles and
includes those policies and procedures that:



•	Pertain to the
maintenance of records that in reasonable detail accurately and fairly reflect the transactions and dispositions of the assets
of the Company;



•	Provide reasonable
assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally
accepted accounting principles, and that receipts and expenditures of the Company are being made only in accordance with authorizations
of management and directors of the Company; and



•	Provide reasonable
assurance regarding prevention or timely detection of unauthorized acquisition, use or disposition of the Company’s assets
that could have a material effect on the financial statements.



Because of its inherent
limitations, internal control over financial reporting may not prevent or detect misstatements. Projections of any evaluation of
effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or
that the degree of compliance with the policies or procedures may deteriorate.



The Company’s management
assessed the effectiveness of the Company’s internal control over financial reporting as of December 31, 2010. In making
this assessment, the Company’s management used the criteria set forth by the Committee of Sponsoring Organizations of the
Treadway Commission (COSO) in Internal Control-Integrated Framework.



Based on our assessment,
management concluded that, as of December 31, 2010, the Company’s internal control over financial reporting is effective
based on those criteria.



This annual report is not
required to include an attestation report of the Company's registered public accounting firm regarding internal control over financial
reporting. This report shall not be deemed to be filed for the purposes of Section 18 of the Exchange Act or otherwise subject
to the liabilities of that section.



Changes in Internal Control Over Financial
Reporting



No change in our internal
control over financial reporting occurred during the year ended December 31, 2010 that has materially affected, or is reasonably
likely to materially affect, our internal control over financial reporting.

15







|Item 9B. | Other Information
|-------- | -----------------



Not applicable.



16





PART III



|Item 10. | Directors, Executive Officers and Corporate Governance
|-------- | ------------------------------------------------------



Directors and Executive Officers

Information regarding the
executive officers and directors of the Company as of February 28, 2011 is set forth below. The biographies of each of the directors
below contain information regarding the person’s service as a director, business experience, director positions held currently
or at any time during the last five years, information regarding involvement in certain legal or administrative proceedings, if
applicable, and the experiences, qualifications, attributes or skills that caused our Board of Directors to determine that the
person should serve as a director of the Company. In addition, all of our directors bring to our Board executive leadership experience
derived from their service as executives of a public company and specifically as an executive of Franklin Street and employee of
FSP Investments, a wholly-owned subsidiary of Franklin Street, as well as other key attributes that are important to an effective
board: integrity, candor, analytical skills, the willingness to engage management and each other in a constructive and collaborative
fashion. In addition, we have included information about each nominee’s specific experience, qualifications, attributes,
or skills that led the board to conclude that he or she should serve as a director of the Company, in light of our business and
structure.



George J. Carter, age 62,
is President and a director of the Company. Since 1996 he has also been President and Chief Executive Officer and a director of
Franklin Street and is responsible for all aspects of the business of Franklin Street and its affiliates, with special emphasis
on the evaluation, acquisition and structuring of real estate investments. From 1992 through 1996 he was President of Boston Financial
Securities, Inc. (“Boston Financial”). Prior to joining Boston Financial, Mr. Carter was owner and developer of Gloucester
Dry Dock, a commercial shipyard in Gloucester, Massachusetts. From 1979 to 1988, Mr. Carter served as Managing Director in charge
of marketing at First Winthrop Corporation, a national real estate and investment banking firm headquartered in Boston, Massachusetts.
Prior to that, he held a number of positions in the brokerage industry including those with Merrill Lynch & Co. and Loeb Rhodes
& Co. Mr. Carter is a graduate of the University of Miami (B.S.). Mr. Carter is a FINRA General Securities Principal (Series
24) and holds a FINRA Series 7 general securities license and a FINRA Series 79, Investment Banker Registration license.



Barbara J. Fournier, age
55, is the Vice President, Chief Operating Officer, Treasurer and Secretary and a director of the Company. Since 1996, she has
also been Chief Operating Officer, Treasurer and Secretary and a director of Franklin Street. In 2008, Ms. Fournier became an Executive
Vice President of Franklin Street. Ms. Fournier has as her primary responsibility, together with Mr. Carter, the management of
all operating business affairs of Franklin Street and its affiliates. From 1993 through 1996, she was Director of Operations for
the private placement division of Boston Financial. Prior to joining Boston Financial, Ms. Fournier served as Director of Operations
for Schuparra Securities Corp. and as the Sales Administrator for Weston Financial Group. From 1979 through 1986, Ms. Fournier
worked at First Winthrop Corporation in administrative and management capacities, including Office Manager, Securities Operations
and Partnership Administration. Ms. Fournier attended Northeastern University and the New York Institute of Finance. Ms. Fournier
is a member of the NYSE Amex Listed Company Council. Ms. Fournier is a FINRA General Securities Principal (Series 24). She also
holds other FINRA supervisory licenses including Series 4 and Series 53, and a FINRA Series 7 general securities license and a
FINRA Series 79, Investment Banker Registration license.



William W. Gribbell, age
51, is an Executive Vice President and a director of the Company. Since 1996, he has been an Executive Vice President of Franklin
Street and has as his primary responsibility the direct equity placement of Franklin Street-sponsored investment programs. From
1993 through 1996 he was an executive officer of Boston Financial. From 1989 to 1993, Mr. Gribbell worked at Winthrop Financial
Associates. Mr. Gribbell is a graduate of Boston University (B.A.). Mr. Gribbell holds a FINRA Series 7 general securities license
and a FINRA Series 79, Investment Banker Registration license.



R. Scott MacPhee, age 53,
is an Executive Vice President and a director of the Company. Since 1996, he has been an Executive Vice President of Franklin Street
and has as his primary responsibility the direct equity placement of Franklin Street-sponsored investment programs. From 1993 through
1996 he was an executive officer of Boston Financial. From 1985 to 1993, Mr. MacPhee worked at Winthrop Financial Associates. Mr.
MacPhee attended American International College. Mr. MacPhee holds a FINRA Series 7 general securities license and a FINRA Series
79, Investment Banker Registration license.



17





Janet Prier Notopoulos,
age 63, is a Vice President and a director of the Company. In addition, she is President of FSP Property Management LLC and an
Executive Vice President and a director of Franklin Street and has as her primary responsibility the oversight of the management
of the real estate assets of Franklin Street and its affiliates. Prior to joining Franklin Street in 1997, Ms. Notopoulos was a
real estate and marketing consultant for various clients. From 1975 to 1983, she was Vice President of North Coast Properties,
Inc., a Boston real estate investment company. Between 1969 and 1973, she was a real estate paralegal at Goodwin, Procter &
Hoar. Ms. Notopoulos is a graduate of Wellesley College (B.A.) and the Harvard School of Business Administration (M.B.A).



Jeffrey B. Carter, age
39, is a Vice President and a director of the Company, and is George J. Carter's son. In addition, he is a Senior Vice President
and the Director of Acquisitions for Franklin Street. Prior to joining Franklin Street in 1998, Mr. Carter worked in Trust Administration
for Northern Trust Bank in Miami, Florida. Mr. Carter is a graduate of Arizona State University (B.A.) and The George Washington
University (M.A.). Mr. Carter holds a FINRA Series 7 general securities license and a FINRA Series 79, Investment Banker Registration
license.



Each of our directors holds
office from the time of his or her election until the next annual meeting and until a successor is elected and qualified, or until
such director’s earlier death, resignation or removal. Each of the above persons has been associated with us in the positions
described above since our inception in 2006. Each of them is an employee of FSP Investments LLC, a wholly-owned subsidiary of Franklin
Street, which is the sole owner of the Common Stock. Each of our officers serves in that capacity at the request of Franklin Street.



Mr. Carter, Ms. Fournier,
Mr. MacPhee, Mr. Gribbell and Ms. Notopoulos also serve as directors of FSP Galleria North Corp., FSP Phoenix Tower Corp. and FSP
303 East Wacker Drive Corp., which are public reporting companies sponsored by Franklin Street. Jeffrey B. Carter also serves as
a director of FSP 303 East Wacker Drive Corp. In their capacities as directors of FSP Galleria North Corp., FSP Phoenix Tower Corp.
and FSP 303 East Wacker Drive Corp., Mr. Carter, Ms. Fournier, Mr. MacPhee, Mr. Gribbell, Ms. Notopoulos and Mr. Carter, as applicable,
each holds office from the time of his or her election until the next annual meeting and until a successor is elected and qualified,
or until such director's earlier death, resignation or removal.



Sections 16(a) Beneficial Ownership Reporting
Compliance



Based solely on its review
of copies of reports filed by the directors and executive officers of the Company pursuant to Section 16(a) of the Exchange Act,
the Company believes that during 2010 all filings required to be made by its reporting persons were timely made in accordance with
the requirements of the Exchange Act.



Corporate Governance



Our board of directors
does not have standing compensation, nominating and corporate governance or audit committees. Our officers are compensated by Franklin
Street in connection with their employment by Franklin Street and serve as our executive officers at Franklin Street’s request.
Our directors are officers of Franklin Street and we do not consider it necessary to establish a nominating committee or a policy
for reviewing nominees recommended by stockholders. We do not have a director who qualifies as an “audit committee financial
expert” under the regulations of the SEC. We have not adopted a code of business conduct or code of ethics for our executive
officers because all of our officers are officers of Franklin Street and are governed by Franklin Street’s code of business
conduct and ethics.



|Item 11. | Executive Compensation
|-------- | ----------------------



Each of the executive officers
of the Company is compensated by Franklin Street in connection with his or her employment by Franklin Street and serves as an executive
officer of the Company at Franklin Street’s request without compensation. Franklin Street is subject to the informational
requirements of the Exchange Act, and, in accordance therewith, files reports and other information with the Securities and Exchange
Commission (SEC). Franklin Street’s common stock is traded on the NYSE Amex under the symbol “FSP”.



|Item 12. | Security Ownership of Certain Beneficial Owners and Management and Related Stockholder Matters
|-------- | ----------------------------------------------------------------------------------------------



The following tables set
forth the beneficial ownership of the Company’s Common Stock and Preferred Stock as of February 28, 2011 by each holder who
beneficially owns more than five percent of the Company’s Common Stock or Preferred Stock, by each director, by each of the
Company’s executive officers and by all current directors and executive officers as a group. To the Company’s knowledge,
no person or group, other than as set forth below, beneficially owns more than five percent of the Company’s Common Stock
or Preferred Stock.

18







|Common Stock                                                                  | Number of Shares |  | Percentage of
|----------------------------------------------------------------------------- | ---------------- |  | -------------
|                                                                              | Beneficially     |  | Outstanding  
|Name of Holder                                                                | Owned            |  | Common Stock 
|                                                                              |                  |  |              
|Franklin Street Properties Corp. (1)                                          | 1                |  | 100%         
|                                                                              |                  |  |              
|George J. Carter(2)                                                           | -                |  | 0%           
|                                                                              |                  |  |              
|Barbara J. Fournier(2)                                                        | -                |  | 0%           
|                                                                              |                  |  |              
|R. Scott MacPhee(2)                                                           | -                |  | 0%           
|                                                                              |                  |  |              
|William W. Gribbell(2)                                                        | -                |  | 0%           
|                                                                              |                  |  |              
|Janet P. Notopoulos(2)                                                        | -                |  | 0%           
|                                                                              |                  |  |              
|Jeffrey B. Carter(2)                                                          | -                |  | 0%           
|                                                                              |                  |  |              
|All Directors and Executive Officers as a Group
 (consisting of 6 persons)(2) | -                |  | 0%           



|Preferred Stock                                                                | Number of Shares |  | Percentage of  
|------------------------------------------------------------------------------ | ---------------- |  | ---------------
|                                                                               | Beneficially     |  | Outstanding    
|Name of Holder                                                                 | Owned            |  | Preferred Stock
|                                                                               |                  |  |                
|George J. Carter(2)                                                            | -                |  | 0%             
|                                                                               |                  |  |                
|Barbara J. Fournier(2)                                                         | -                |  | 0%             
|                                                                               |                  |  |                
|R. Scott MacPhee(2)                                                            | -                |  | 0%             
|                                                                               |                  |  |                
|William W. Gribbell(2)                                                         | -                |  | 0%             
|                                                                               |                  |  |                
|Janet P. Notopoulos(2)                                                         | -                |  | 0%             
|                                                                               |                  |  |                
|Jeffery B. Carter(2)                                                           | -                |  | 0%             
|                                                                               |                  |  |                
|All Directors and Executive Officers as a Group 
(consisting of 6 persons) (2) | -                |  | 0%             



(1)	The
address of Franklin Street Properties Corp. is401 Edgewater Place, Wakefield, Massachusetts 01880.

(2)	Each
of the Executive Officers is employed by FSP Investments LLC, a subsidiary of Franklin Street Properties Corp. Franklin Street
Properties Corp. owns 100% of the issued and outstanding Common Stock of the Company.



Equity Compensation Plan Information



The Company does not have any equity
compensation plans.



19







|Item 13. | Certain Relationships and Related Transactions, and Director Independence
|-------- | -------------------------------------------------------------------------



Certain Relationships and Related Transactions



Messrs. George J. Carter,
R. Scott MacPhee and William W. Gribbell and Mses. Barbara J. Fournier and Janet P. Notopoulos, each of whom is an executive officer
and a director of the Company, are executive officers of Franklin Street and, except for Messrs. R. Scott MacPhee and William W.
Gribbell, are directors of Franklin Street. In addition, Jeffrey B. Carter, a vice president and a director of the Company, is
a senior vice president and Director of Acquisitions of Franklin Street but not a director of Franklin Street. Jeffrey B. Carter
is George J. Carter’s son. None of such persons received any remuneration from the Company for their services.



We have in the past engaged
in and currently engage in transactions with a related party, Franklin Street and its subsidiaries FSP Investments LLC and FSP
Property Management LLC, which we refer to collectively as FSP. We expect to continue to have related party transactions with FSP
in the form of management fees paid to FSP to manage the Company on behalf of our stockholders. FSP Property Management LLC currently
provides the Company with asset management and financial reporting services. The asset management agreement between the Company
and FSP Property Management LLC requires the Company to pay FSP Property Management LLC a monthly fee equal to one percent (1%)
of the gross revenues of the Property. The asset management agreement between the Company and FSP Property Management LLC may be
terminated by either party without cause at any time, upon at least thirty (30) days written notice, effective at the end of the
notice period. For the years ended December 31, 2010 and 2009, management fees paid were $161,000 and $162,000, respectively.



Franklin Street is the
sole holder of the Company’s one share of Common Stock that is issued and outstanding. Subsequent to the completion of the
private placement of the Preferred Stock in January 2007, Franklin Street has not been entitled to share in any earnings or any
dividend as a result of its ownership of the Common Stock of the Company.



Director Independence



Our securities are not
listed on a national securities exchange or in an inter-dealer quotation system. None of our directors qualifies as “independent”
under the standards of the NYSE Amex, where Franklin Street is listed.



|Item 14. | Principal Accounting Fees and Services
|-------- | --------------------------------------



Independent Auditor Fees and Other
Matters

The following tables summarize
the aggregate fees billed by the Company’s independent registered public accounting firm, Braver PC, for audit services for
each of the last two fiscal years and for other services rendered to the Company in each of the last two fiscal years.



|Fee Category           |  | 2010 |        | 2009
|---------------------- |  | ---- | ------ | ----
|Audit Fees (1)         |  | $    | 64,050 |     
|Audit-Related Fees (2) |  |      |        |     
|Tax fees (3)           |  | $    | 5,250  |     
|All Other Fees (4)     |  |      |        |     
|Total Fees             |  | $    | 69,300 |     



(1)	Audit
fees consist of fees for the audit of our financial statements, the review of the interim financial statements included in our
quarterly reports on Form 10-Q, and other professional services provided in connection with statutory and regulatory filings or
engagements.



(2)	Audit-related
fees consist of fees for assurance and related services that are reasonably related to the performance of the audit and the review
of our financial statements and which are not reported under “Audit Fees”.



20





(3)	Tax
fees consist of fees for tax compliance, tax advice and tax planning services. Tax compliance services, which relate to the preparation
of tax returns, claims for refunds and tax payment-planning services, accounted for $5,250 of the total tax fees incurred in 2010
and 2009.



(4)	The
Company was not billed by its independent registered public accounting firm in 2010 or 2009 for any other fees.



Pre-Approval Policy and Procedures



The Company has not
adopted policies and procedures relating to the pre-approval of audit and non-audit services that are to be performed by the Company’s
independent registered public accounting firm.





21





PART IV



|Item 15. | Exhibits, Financial Statement Schedules
|-------- | ---------------------------------------



(a)	The
following documents are filed as part of this report.



1.Financial
Statements: The Financial Statements listed in the accompanying Index to Consolidated Financial Statements are filed as part of
this Annual Report on Form 10-K.



2.Financial
Statement Schedule: The Financial Statement Schedule listed on the accompanying Index to Consolidated Financial Statements is filed
as part of this Annual Report on Form 10-K.



3.Exhibits:
The Exhibits listed in the Exhibit Index are filed as part of this Annual Report on Form 10-K.





22





SIGNATURES

Pursuant to the requirements of Section
13 or 15(d) of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf as of
March 11, 2011 by the undersigned, thereunto duly authorized.

FSP 50 South Tenth Street Corp.

By: /s/ George J. Carter

George J. Carter

President



Pursuant to the requirements of the
Securities Exchange Act of 1934, this report has been signed by the following persons on behalf of the registrant and in the capacities
and on the dates indicated.

|Signature               |  | Title                                                                                                                                                             |  | Date          
|----------------------- |  | ----------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | --------------
|                        |  |                                                                                                                                                                   |  |               
|/s/ George J. Carter    |  | President and Director
        (Principal Executive Officer)                                                                                                      |  | March 11, 2011
|George J. Carter        |  |                                                                                                                                                                   | 
|                        |  |                                                                                                                                                                   |  |               
|/s/ Barbara J. Fournier |  | Vice President, Chief Operating Officer,
        Treasurer, Secretary and Director
        (Principal Financial Officer and Principal
        Accounting Officer) |  | March 11, 2011
|Barbara J. Fournier     |  |                                                                                                                                                                   | 
|                        |  |                                                                                                                                                                   |  |               
|/s/ R. Scott MacPhee    |  | Director, Executive Vice President                                                                                                                                |  | March 11, 2011
|R. Scott MacPhee        |  |                                                                                                                                                                   |  |               
|                        |  |                                                                                                                                                                   |  |               
|/s/ William W. Gribbell |  | Director, Executive Vice President                                                                                                                                |  | March 11, 2011
|William W. Gribbell     |  |                                                                                                                                                                   |  |               
|                        |  |                                                                                                                                                                   |  |               
|/s/ Janet P. Notopoulos |  | Director, Vice President                                                                                                                                          |  | March 11, 2011
|Janet P. Notopoulos     |  |                                                                                                                                                                   |  |               
|                        |  |                                                                                                                                                                   |  |               
|/s/ Jeffrey B. Carter   |  | Director, Vice President                                                                                                                                          |  | March 11, 2011
|Jeffrey B. Carter       |  |                                                                                                                                                                   |  |               



23





EXHIBIT INDEX

|Exhibit No. | Description                                                                                                                                                                                                                                             
|----------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
|            |                                                                                                                                                                                                                                                         
|3.1         | Amended and Restated Certificate of Incorporation,
        incorporated herein by reference to Exhibit 3.1 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as
        amended (File No. 000-52551)                              
|3.2         | By-Laws, incorporated herein by reference to
        Exhibit 3.2 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File No. 000-52551)                                                                                
|4.1         | Loan Agreement, incorporated herein by reference
        to Exhibit 4.1 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File No. 000-52551)                                                                         
|4.2         | Mortgage, Assignment of Leases and Rents, Security
        Agreement and Fixture Filing, incorporated herein by reference to Exhibit 4.2 to FSP 50 South Tenth Street Corp.’s Registration
        Statement on Form 10, as amended (File No. 000-52551)
|4.3         | Promissory Note, incorporated herein by reference
        to Exhibit 4.3 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File No. 000-52551)                                                                        
|10.1        | Ryan Lease, as amended, incorporated herein
        by reference to Exhibit 10.1 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File No.
        000-52551)                                                        
|10.2        | Oracle America Lease, as amended, incorporated
        herein by reference to Exhibit 10.2 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File
        No. 000-52551)                                              
|10.3        | Asset Management Agreement, incorporated herein
        by reference to Exhibit 10.3 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File No.
        000-52551)                                                    
|10.4        | Management Agreement, incorporated herein by
        reference to Exhibit 10.4 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File No. 000-52551)                                                                  
|10.5        | Voting Agreement, incorporated herein by reference
        to Exhibit 10.5 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File No. 000-52551)                                                                      
|21.1        | Subsidiaries of the Registrant, incorporated
        herein by reference to Exhibit 21.1 to FSP 50 South Tenth Street Corp.’s Registration Statement on Form 10, as amended (File
        No. 000-52551)                                                
|31.1        | Certification of FSP 50 South Tenth Street
        Corp.'s principal executive officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                                                                        
|31.2        | Certification of FSP 50 South Tenth Street
        Corp.'s principal financial officer pursuant to Section 302 of the Sarbanes-Oxley Act of 2002                                                                                                        
|32.1        | Certification of FSP 50 South Tenth Street
        Corp.'s principal executive officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley
        Act of 2002                                                 
|32.2        | Certification of FSP 50 South Tenth Street Corp.'s principal financial officer pursuant to 18 U.S.C. Section 1350, as adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002                                                                 



24





FSP 50 South Tenth Street Corp.

Index to Consolidated Financial Statements



Table of Contents



|                                                                                                          |  | Page
|--------------------------------------------------------------------------------------------------------- |  | ----
|Consolidated Financial Statements                                                                         |  |     
|                                                                                                          |  |     
|Report of Independent Registered Public Accounting Firm                                                   |  | F-2 
|                                                                                                          |  |     
|Consolidated Balance Sheets as of December 31, 2010 and 2009                                              |  | F-3 
|                                                                                                          |  |     
|Consolidated Statements of Operations for the years ended December 31, 2010 and 2009                      |  | F-4 
|                                                                                                          |  |     
|Consolidated Statements of Changes in Stockholders’ Equity for the years ended December 31, 2009 and 2010 |  | F-5 
|                                                                                                          |  |     
|Consolidated Statements of Cash Flows for the years ended December 31, 2010 and 2009                      |  | F-6 
|                                                                                                          |  |     
|Notes to Consolidated Financial Statements                                                                |  | F-7 
|                                                                                                          |  |     
|Financial Statement Schedule – Schedule III                                                               |  | F-15



F-1





[LETTERHEAD
OF BRAVER PC]





REPORT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING
FIRM





To the Stockholders

FSP 50 South Tenth Street Corp.

Wakefield, Massachusetts





We have audited the accompanying consolidated
balance sheets of FSP 50 South Tenth Street Corp. as of December 31, 2010 and 2009, and the related consolidated statements of
operations, changes in stockholders’ equity and cash flows for the years then ended. Our audits also included the financial
statement schedule listed in the Index at Item 15(a)(2). These consolidated financial statements and schedule are the responsibility
of the Company’s management. Our responsibility is to express an opinion on these consolidated financial statements and schedule
based on our audits.



We conducted our audits in accordance with
the standards of the Public Company Accounting Oversight Board (United States). Those standards require that we plan and perform
the audits to obtain reasonable assurance about whether the consolidated financial statements are free of material misstatement.
The Company is not required to have, nor were we engaged to perform, an audit of its internal control over financial reporting.
Our audits included consideration of internal control over financial reporting as a basis for designing audit procedures that are
appropriate in the circumstances, but not for the purpose of expressing an opinion on the effectiveness of the Company’s
internal control over financial reporting. Accordingly, we express no such opinion. An audit includes examining, on a test basis,
evidence supporting the amounts and disclosures in the consolidated financial statements. An audit also includes assessing the
accounting principles used and significant estimates made by management, as well as evaluating the overall financial statement
presentation. We believe that our audits provide a reasonable basis for our opinion.



In our opinion, the consolidated financial
statements referred to above present fairly, in all material respects, the financial position of FSP 50 South Tenth Street Corp.
as of December 31, 2010 and 2009, and the results of its operations and its cash flows for the years then ended in conformity with
accounting principles generally accepted in the United States of America. Also, in our opinion, the related financial statement
schedule, when considered in relation to the basic consolidated financial statements taken as a whole, presents fairly in all material
respects the information set forth therein.





/s/ Braver PC

Newton, Massachusetts

March 11, 2011

F-2





FSP 50 South Tenth Street Corp.
Consolidated Balance Sheets



|                                                                                                                 |  | December 31,
|---------------------------------------------------------------------------------------------------------------- |  | ------------
|(in thousands, except share and par value amounts)                                                               |  | 2010        
|                                                                                                                 |  |             
|Assets:                                                                                                          |  |             
|Real estate investments, at cost:                                                                                |  |             
|Land                                                                                                             |  | $           
|Buildings and improvements                                                                                       |  |             
|                                                                                                                 |  |             
|Less accumulated depreciation                                                                                    |  |             
|Real estate investments, net                                                                                     |  |             
|                                                                                                                 |  |             
|Acquired real estate leases, net of accumulated       amortization of $3,034 and $2,744, respectively            |  |             
|Acquired favorable real estate leases, net of accumulated        amortization of $1,705 and $1,447, respectively |  |             
|Cash and cash equivalents                                                                                        |  |             
|Cash - held in escrow                                                                                            |  |             
|Tenant rent receivable, less allowance        for doubtful accounts of $13 and $30, respectively                 |  |             
|Step rent receivable                                                                                             |  |             
|Deferred leasing costs, net of accumulated      amortization of $51 and $20, respectively                        |  |             
|Deferred financing costs, net of accumulated      amortization of $237 and $177, respectively                    |  |             
|Prepaid expenses and other assets                                                                                |  |             
|Total assets                                                                                                     |  | $           
|                                                                                                                 |  |             
|Liabilities and Stockholders’ Equity:                                                                            |  |             
|                                                                                                                 |  |             
|Liabilities:                                                                                                     |  |             
|Accounts payable and accrued expenses                                                                            |  | $           
|Tenant security deposits                                                                                         |  |             
|Loan payable                                                                                                     |  |             
|Acquired unfavorable real estate leases, net of accumulated        amortization of $777 and $593, respectively   |  |             
|Total liabilities                                                                                                |  |             
|                                                                                                                 |  |             
|Commitments and Contingencies:                                                                                   |  |             
|                                                                                                                 |  |             
|Stockholders’ Equity:                                                                                            |  |             
|Preferred Stock, $.01 par value, 1,540 shares                                                                    |  |             
|authorized, 700 shares issued and outstanding                                                                    |  |             
|at December 31, 2010 and 2009, aggregate                                                                         |  |             
|liquidation preference $70,000                                                                                   |  |             
|                                                                                                                 |  |             
|Common Stock, $.01 par value, 1 share                                                                            |  |             
|authorized, issued and outstanding                                                                               |  |             
|Additional paid-in capital                                                                                       |  |             
|Retained earnings (deficit) and
    distributions in excess of earnings                                          |  |             
|Total Stockholders’ Equity                                                                                       |  |             
|                                                                                                                 |  |             
|Total Liabilities and Stockholders’ Equity                                                                       |  | $           
|See accompanying notes to consolidated financial statements.                                                    



F-3







FSP 50 South Tenth Street Corp.
Consolidated Statements of Operations



|                                                             |  | For the Year Ended December 31,
|------------------------------------------------------------ |  | -------------------------------
|(in thousands, except share and per share amounts)           |  | 2010                           
|                                                             |  |                                
|Revenues:                                                    |  |                                
|Rental                                                       |  | $                              
|                                                             |  |                                
|Total revenue                                                |  |                                
|                                                             |  |                                
|Expenses:                                                    |  |                                
|                                                             |  |                                
|Rental operating expenses                                    |  |                                
|Real estate taxes and insurance                              |  |                                
|Depreciation and amortization                                |  |                                
|Interest expense                                             |  |                                
|                                                             |  |                                
|Total expenses                                               |  |                                
|                                                             |  |                                
|Net income before interest income                            |  |                                
|                                                             |  |                                
|Interest income                                              |  |                                
|                                                             |  |                                
|Net income attributable to preferred stockholders            |  | $                              
|                                                             |  |                                
|Weighted average number of preferred shares outstanding,     |  |                                
|basic and diluted                                            |  |                                
|                                                             |  |                                
|Net income per preferred share, basic and diluted            |  | $                              
|See accompanying notes to consolidated financial statements.





F-4







FSP 50 South Tenth Street Corp.

Consolidated Statements of Changes in Stockholders'
Equity

For the Years Ended December 31, 2009 and
2010



|(in thousands, except per share amounts)                     |  | Preferred  Stock |   | Common  Stock |  | Additional  Paid-in Capital |   | Retained  Earnings 
(Deficit)
    and  Distributions in Excess of  Earnings |  | Total  Stockholders' Equity
|------------------------------------------------------------ |  | ---------------- | - | ------------- |  | --------------------------- | - | --------------------------------------------------------------------------- |  | ---------------------------
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|Balance, January 1, 2009                                     |  | $                | — |               |  | $                           | — |                                                                             |  | $                          
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|Distributions - preferred stockholders                       |  |                  |   |               |  |                             |   |                                                                             |  |                            
|or $7,000 per preferred share                                |  |                  | — |               |  |                             | — |                                                                             |  |                            
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|Net income                                                   |  |                  | — |               |  |                             | — |                                                                             |  |                            
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|Balance, December 31, 2009                                   |  |                  | — |               |  |                             | — |                                                                             |  |                            
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|Distributions - preferred stockholders                       |  |                  |   |               |  |                             |   |                                                                             |  |                            
|or $7,000 per preferred share                                |  |                  | — |               |  |                             | — |                                                                             |  |                            
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|Net income                                                   |  |                  | — |               |  |                             | — |                                                                             |  |                            
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|Balance, December 31, 2010                                   |  | $                | — |               |  | $                           | — |                                                                             |  | $                          
|                                                             |  |                  |   |               |  |                             |   |                                                                             |  |                            
|See accompanying notes to consolidated financial statements.



F-5





FSP 50 South Tenth Street Corp.
Consolidated Statements of Cash Flows



|                                                             |  | For the Year Ended December 31,
|------------------------------------------------------------ |  | -------------------------------
|(in thousands)                                               |  | 2010                           
|Cash flows from operating activities:                        |  |                                
|Net income                                                   |  | $                              
|Adjustments to reconcile net income to net cash              |  |                                
|provided by operating activities:                            |  |                                
|Depreciation and amortization                                |  |                                
|Amortization of favorable real estate leases                 |  |                                
|Amortization of unfavorable real estate leases               |  |                                
|Increase (decrease) in bad debt reserve                      |  |                                
|Changes in operating assets and liabilities:                 |  |                                
|Cash - held in escrow                                        |  |                                
|Tenant rent receivable                                       |  |                                
|Step rent receivable                                         |  |                                
|Prepaid expenses and other assets                            |  |                                
|Accounts payable and accrued expenses                        |  |                                
|Tenant security deposits                                     |  |                                
|Payment of deferred leasing costs                            |  |                                
|                                                             |  |                                
|Net cash provided by operating activities                    |  |                                
|Cash flows from investing activities:                        |  |                                
|Purchase of real estate assets                               |  |                                
|                                                             |  |                                
|Net cash used for investing activities                       |  |                                
|Cash flows from financing activities:                        |  |                                
|Distributions to stockholders                                |  |                                
|Net cash used for financing activities                       |  |                                
|Net increase (decrease) in cash and cash equivalents         |  |                                
|Cash and cash equivalents, beginning of year                 |  |                                
|Cash and cash equivalents, end of year                       |  | $                              
|Supplemental disclosure of cash flow information:            |  |                                
|Cash paid for interest                                       |  | $                              
|                                                             |  |                                
|Disclosure of non-cash operating activities:                 |  |                                
|Accrued costs for purchase of real estate assets             |  | $                              
|                                                             |  |                                
|See accompanying notes to consolidated financial statements.







F-6





FSP 50 South Tenth Street Corp.

Notes to Consolidated Financial
Statements



1.      Organization



FSP 50 South Tenth Street
Corp. (the “Company”) was organized on September 12, 2006 as a corporation under the laws of the State of Delaware
to purchase, own and operate a twelve-story multi-tenant office and retail building containing approximately 498,768 rentable square
feet of space located in downtown Minneapolis, Minnesota (the “Property”). The Company acquired the Property on November
8, 2006. Franklin Street Properties Corp. (“Franklin Street”) (NYSE Amex: FSP) holds the sole share of the Company’s
common stock, $.01 par value per share (the “Common Stock”). Between November 2006 and January 2007, FSP Investments
LLC (member, FINRA and SIPC), a wholly-owned subsidiary of Franklin Street, completed the sale on a best efforts basis of 700 shares
of the Company’s preferred stock, $.01 par value per share (the “Preferred Stock”). FSP Investments LLC sold
the Preferred Stock in a private placement offering to “accredited investors” within the meaning of Regulation D under
the Securities Act of 1933.



All references to the Company refer to FSP
50 South Tenth Street Corp. and its consolidated subsidiary, collectively, unless the context otherwise requires.



2.     Summary
of Significant Accounting Policies



BASIS OF PRESENTATION



The accompanying
consolidated financial statements include all of the accounts of the Company and its wholly-ownedsubsidiary.
All significant intercompany accounts and transactions have been eliminated in consolidation.



ESTIMATES AND ASSUMPTIONS



The Company prepares its consolidated financial
statements and related notes in conformity with accounting principles generally accepted in the United States of America (“GAAP”).
These principles require management to make estimates and assumptions that affect the reported amounts of assets and liabilities
and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts
of revenue and expenses during the reporting period. Actual results could differ from those estimates.



REAL ESTATE AND DEPRECIATION



Real estate assets are stated at the lower
of cost or fair value, as appropriate, less accumulated depreciation.



Costs related to property acquisition and improvements
are capitalized. Typical capital items include new roofs, site improvements, various exterior building improvements and major interior
renovations. Funding for capital improvements typically is provided by cash set aside at the time the Property was purchased.



Routine replacements and ordinary maintenance
and repairs that do not extend the life of the asset are expensed as incurred. Funding for repairs and maintenance items typically
is provided by cash flows from operating activities.



Depreciation is computed using the straight-line
method over the assets' estimated useful lives as follows:



|Category              | Years
|--------------------- | -----
|Building - Commercial | 39   
|Building Improvements | 15-39
|Furniture & Equipment | 5-7  



The Company reviews the Property to determine
if the carrying amount will be recovered from future cash flows if certain indicators of impairment are identified at the Property.
The evaluation of anticipated cash flows is highly subjective and is based in part on assumptions regarding future occupancy, rental
rates and capital requirements that could differ materially from actual results in future periods. When indicators of impairment
are present and the sum of the undiscounted future cash flows is less than the carrying value of such asset, an impairment loss
is recorded equal to the difference between the asset’s current carrying value and its fair value based on discounting its
estimated future cash flows. At December 31, 2010 and 2009, no impairment charges were recorded.



Depreciation expense of $2,573,000 and $2,519,000
is included in Depreciation and Amortization in the Company’s Consolidated Statements of Operations for the years ended December
31, 2010 and 2009, respectively.

F-7





FSP 50 South Tenth Street Corp.

Notes to Consolidated Financial Statements



2.
Summary of Significant Accounting Policies (continued)

ACQUIRED REAL ESTATE LEASES



The acquired real estate leases represent the
estimated value of legal and leasing costs related to acquired leases that were included in the purchase price when the Company
acquired the Property. The Company subsequently amortizes these costs on a straight-line basis over the remaining lives of the
related leases. Amortization expense of $782,000 and $976,000 is included in Depreciation and Amortization in the Company’s
Consolidated Statements of Operations for the years ended December 31, 2010 and 2009, respectively.



Acquired real estate lease costs included in
the purchase price of the Property were $6,447,000. Detail of the acquired real estate leases are as follows:



|                         |  | December 31,
|------------------------ |  | ------------
|(in thousands)           |  | 2010        
|Cost                     |  | $           
|Accumulated amortization |  |             
|Book value               |  | $           



The estimated annual amortization expense for
the five years succeeding December 31, 2010 is as follows:



|(in thousands) |               
|-------------- | --------------
|2011           | $          703
|2012           | $          636
|2013           | $          636
|2014           | $          311
|2015           | $          111



ACQUIRED FAVORABLEREAL
ESTATE LEASES



Acquired favorable real estate leases
represent the value related to the leases when the lease payments due under a tenant’s lease exceed the market rate of the
lease at the date the Property was acquired. The Company reports this value separately from its investment in real estate. The
Company subsequently amortizes this amount on a straight-line basis over the remaining life of the tenant’s lease. Amortization
of $424,000 and $461,000 is shown as a reduction of rental income in the Company’s Consolidated Statements of Operations
for the years ended December 31, 2010 and 2009, respectively.



The acquired favorable real estate leases included
in the purchase price of the property were $3,198,000. Detail of the acquired favorable real estate leases are as follows:



|                         |  | December 31,
|------------------------ |  | ------------
|(in thousands)           |  | 2010        
|Cost                     |  | $           
|Accumulated amortization |  |             
|Book value               |  | $           





F-8





FSP 50 South Tenth Street Corp.

Notes to Consolidated Financial Statements



2.     Summary
of Significant Accounting Policies (continued)



ACQUIRED FAVORABLE REAL ESTATE LEASES (continued)



The estimated annual amortization expense for
the five years succeeding December 31, 2010 is as follows:



|(in thousands) |                  
|-------------- | -----------------
|2011           | $            401 
|2012           | $            346 
|2013           | $            346 
|2014           | $            116 
|2015           | $              17



ACQUIRED UNFAVORABLE REAL ESTATE LEASES



Acquired unfavorable real estate leases represent
the value relating to leases with rents below the market rate at the time of property acquisition. Amortization is computed using
the straight-line method over the lives of the leases assumed. Amortization of $187,000 and $197,000 is included with rental revenue
in the Company’s Consolidated Statements of Operations for the years ended December 31, 2010 and 2009, respectively.



The acquired unfavorable real estate leases
included in the purchase price of the property were $1,482,000. Detail of the acquired unfavorable real estate leases are as follows:



|                         |  | December 31,
|------------------------ |  | ------------
|(in thousands)           |  | 2010        
|Cost                     |  | $           
|Accumulated amortization |  |             
|Book value               |  | $           



The estimated annual amortization expense for
the five years succeeding December 31, 2010 is as follows:



|(in thousands) |                  
|-------------- | -----------------
|2011           | $            175 
|2012           | $            140 
|2013           | $            140 
|2014           | $            140 
|2015           | $              71



CASH AND CASH EQUIVALENTS



The Company considers all
highly liquid debt instruments with an initial maturity of three months or less to be cash equivalents. The Company has set aside
funded reserves of $7,193,000 and $7,799,000 at December 31, 2010 and 2009, respectively, in anticipation of future capital needs
of the Property. These funds typically are used for the payment of real estate assets and deferred leasing commissions; however,
there is no legal restriction on their use and they may be used for any Company purpose.



CASH - HELD IN ESCROW



The Company is required under its loan documents
to make monthly deposits into a pledge account for real estate taxes. The amount held in escrow for real estate taxes was $1,388,000
and $1,072,000 as of December 31, 2010 and 2009, respectively.



F-9





FSP 50 South Tenth Street Corp.

Notes to Consolidated Financial Statements



2.     Summary of Significant Accounting
Policies (continued)



CONCENTRATION OF CREDIT RISKS



Cash, cash equivalents and short-term investments
are financial instruments that potentially subject the Company to a concentration of credit risk. The Company maintains its cash
balances and short-term investments principally in banks which the Company believes to be creditworthy. The Company periodically
assesses the financial condition of these banks and believes that the risk of loss is minimal. Cash balances held with various
financial institutions frequently exceed the insurance limit of $250,000 provided by the Federal Deposit Insurance Corporation.



For the years ended December 31, 2010 and 2009,
rental income was derived from various tenants. As such, future receipts are dependent upon the financial strength of the lessees
and their ability to perform under the lease agreements.



The following tenants represent greater than
10% of rental revenue as of December 31:



|               | 2010 | 2009
|-------------- | ---- | ----
|Oracle America | 51%  | 51% 
|Ryan Companies | 18%  | 18% 



FINANCIAL INSTRUMENTS



The Company estimates that the carrying value
of cash and cash equivalents, cash-held in escrow, and loan payable approximate their fair values based on their short-term maturity
and prevailing interest rates.



STEP RENT RECEIVABLE



Certain leases provide
for fixed rental increases over the life of the lease. Rental revenue is recognized on the straight-line basis over the related
lease term; however, billings by the Company are based on required minimum rentals in accordance with the lease agreements. Step
rent receivable, which is the cumulative revenue recognized in excess of amounts billed by the Company, is $665,000 and $602,000
at December 31, 2010 and 2009, respectively.



TENANT RENT RECEIVABLE



Tenant rent and other receivables are reported
at the amount the Company expects to collect on balances outstanding at year-end. The Company provides
an allowance for doubtful accounts based on its estimate of a tenant’s ability to make future rent payments. The computation
of this allowance is based in part on the tenants’ payment history and current credit status.Management monitors
outstanding balances and relationships and concluded that an allowance of $13,000 and $30,000 as of December 31, 2010 and 2009,
respectively, is sufficient.



DEFERRED LEASING COSTS



Deferred leasing
commissions represent direct and incremental external leasing costs incurred in the leasing of commercial space. These costs are
capitalized and are amortizedon a straight-line basis over the terms of the related lease agreements. Deferred leasing
costs of $189,000 and $174,000 were incurred during the years ended December 31, 2010 and 2009, respectively. Amortization expense
was $31,000 and $15,000 for the years ended December 31, 2010 and 2009, respectively.



SYNDICATION FEES



Syndication fees are selling commissions and
other costs associated with the initial offering of shares of the Company’s Preferred Stock. Such costs, in the amount of
$5,786,000 have been reported as a reduction in Stockholders’ Equity in the Company’s consolidated balance sheets.





F-10





FSP 50 South Tenth Street Corp.

Notes to Consolidated Financial Statements



2.	Summary of Significant
Accounting Policies (continued)



REVENUE RECOGNITION



The Company has retained substantially all
of the risks and benefits of ownership of the Company's commercial property and accounts for its leases as operating leases. Rental
income from the leases, which may include rent concessions (including free rent) and scheduled increases in rental rates during
the lease term, is recognized on a straight-line basis. Any lease incentives are recorded as deferred rent and amortized as reductions
to rental income over the lease term on a straight-line basis. The Company does not have any percentage rent arrangements with
its commercial property tenants. Reimbursable costs are included in rental income in the year earned. A schedule showing the components
of rental revenue is shown below.



|                                   |  | Year Ended December 31,
|---------------------------------- |  | -----------------------
|(in thousands)                     |  | 2010                   
|Income from leases                 |  | $                      
|Straight-line rent adjustment      |  |                        
|Reimbursable expenses              |  |                        
|Amortization of favorable leases   |  |                        
|Amortization of unfavorable leases |  |                        
|                                   |  |                        
|Total                              |  | $                      



INTEREST INCOME



Interest income is recognized when the earnings
process is complete.



INCOME TAXES



The Company intends to elect to be taxed as
a Real Estate Investment Trust (“REIT”) under the Internal Revenue Code of 1986, as amended. As a REIT, the Company
generally is entitled to a tax deduction for dividends paid to its stockholders, thereby effectively subjecting the distributed
net income of the Company to taxation at the stockholder level only. The Company must comply with a variety of restrictions to
maintain its status as a REIT. These restrictions include the type of income it can earn, the type of assets it can hold, the number
of stockholders it can have and the concentration of their ownership, and the amount of the Company’s taxable income that
must be distributed annually.



NET INCOME PER SHARE

Basic net income per share of Preferred Stock
is computed by dividing net income by the weighted average number of shares of Preferred Stock outstanding during the period. Diluted
net income per share of Preferred Stock reflects the potential dilution that could occur if securities or other contracts to issue
shares were exercised or converted into shares. There were no potential dilutive shares outstanding at December 31, 2010 or 2009.
Subsequent to the completion of the offering shares of Preferred Stock, the holders of Common Stock are not entitled to share in
any income nor in any related dividend.



SUBSEQUENT EVENTS



In preparing these consolidated financial statements
the Company evaluated events that occurred through the date of issuance of these financial statements, for potential
recognition or disclosure.



F-11





FSP 50
South Tenth Street Corp.

Notes to Consolidated Financial Statements



3.     Loan Payable



The Company has a loan agreement (the “Loan”)
outstanding with Bank of America, N.A. in the amount of $76,200,000. Loan payments are interest-only until the Loan matures and
bears interest at the fixed rate of 5.287% per annum. The Loan is secured by the Property. The Loan was entered into on December
21, 2006 and matures on January 1, 2012, with the entire principal balance due on that date. Interest expense for the years ended
December 31, 2010 and 2009 was $4,085,000 and $4,086,000, respectively.



The Loan includes restrictions on property
liens and requires compliance with various financial covenants. Financial covenants include the requirement that the Company deposit
all rents or other revenue from the Property to a lockbox account with the lender and provide periodic reporting. The Loan has
certain restrictions on the Company’s ability to incur debt. The Company was in compliance with all loan covenants as of
December 31, 2010 and 2009.



4.     Income Taxes



The Company has elected to
be taxed as a REIT under Sections 856-860 of the Internal Revenue Code of 1986, as amended. In order to qualify as a REIT, the
Company is required to distribute at least 90% of its taxable income to stockholders and to meet certain asset and income tests
as well as certain other requirements. The Company will generally not be liable for federal income taxes, provided it satisfies
these requirements. Even as a qualified REIT, the Company is subject to certain state and local taxes on its income and property.



The Company adopted an accounting pronouncement
related to uncertainty in income taxes effective January 1, 2007, which did not result in recording a liability, nor was any accrued
interest and penalties recognized with the adoption. Accrued interest and penalties will be recorded as income tax expense, if
the Company records a liability in the future. The Company’s effective tax rate was not affected by the adoption. The Company
files income tax returns in the U.S. federal jurisdiction and the State of Minnesota jurisdiction. The statute of limitations for
the Company’s income tax returns is generally three years and as such, the Company’s returns that remain subject to
examination would be from 2007 and thereafter.



For the period ended December 31, 2006, the
Company incurred a net operating loss for income tax purposes of approximately $4,166,000 that can be carried forward until it
expires in the year 2026.



At December 31, 2010, the Company’s net
tax basis of its real estate assets was $112,990,000.



The following schedule reconciles net
income to taxable income subject to dividend requirements, which are calculated annually:



|                                                   |  | Year Ended December 31,
|-------------------------------------------------- |  | -----------------------
|(in thousands)                                     |  | 2010                   
|                                                   |  |                        
|Net income                                         |  | $                      
|                                                   |  |                        
|Add:   Book depreciation and amortization          |  |                        
|Amortization of favorable real estate leases       |  |                        
|Deferred rent                                      |  |                        
|Bad debt expenses                                  |  |                        
|Less:   Tax depreciation and amortization          |  |                        
|Amortization of
    unfavorable real estate leases |  |                        
|Straight-line rents                                |  |                        
|Taxable income                                     |  | $                      



F-12





FSP 50
South Tenth Street Corp.

Notes to Consolidated Financial Statements



4.     Income Taxes
(continued)



The following schedule summarizes the tax components of the distributions
paid for the year ended December 31,:



|(dollars in thousands) |  | 2010 |           | 2009
|---------------------- |  | ---- | --------- | ----
|                       |  |      | Preferred |     
|Ordinary income        |  | $    | 1,042     |     
|Return of Capital      |  |      | 3,858     |     
|Total                  |  | $    | 4,900     |     



5.     Capital Stock



PREFERRED STOCK



Generally, each holder of shares of Preferred
Stock is entitled to receive ratably all dividends, if any, declared by the Board of Directors out of funds legally available.
The right to receive dividends is non-cumulative, and no right to dividends shall accrue by reason of the fact that no dividend
has been declared in any prior year. Each holder of shares of Preferred Stock will be entitled to receive, to the extent that funds
are available therefore, $100,000 per share of Preferred Stock, before any payment to the holder of Common Stock, out of distributions
to stockholders upon liquidation, dissolution or the winding up of the Company; the balance of any such funds available for distribution
will be distributed among the holders of shares of Preferred Stock and the holder of Common Stock, pro rata based on the number
of shares held by each; provided, however, that for these purposes, one share of Common Stock will be deemed to equal one-tenth
of a share of Preferred Stock.



In addition to certain rights to remove and
replace directors, the holders of a majority of the then outstanding shares of Preferred Stock shall have the further right to
approve or disapprove a proposed sale of the Property, the merger of the Company with any other entity and amendments to the corporate
charter. A vote of the holders of not less than 66.67% of then outstanding shares of Preferred Stock is required for the issuance
of any additional shares of capital stock other than the remaining 840 shares of authorized but unissued Preferred Stock. Holders
of shares of Preferred Stock have no redemption or conversion rights.



COMMON STOCK



Franklin Street is the sole holder of the Company’s
Common Stock. Franklin Street has the right to vote to elect the directors of the Company and to vote on all matters, subject to
the voting rights of the Preferred Stock set forth above. Subsequent to the completion of the offering of the shares of Preferred
Stock in January 2007, Franklin Street, as the holder of Common Stock, was not entitled to share in any earnings nor any related
dividend.



6.     Related Party Transactions



The Company has in the past engaged in and
currently engages in transactions with a related party, Franklin Street and its subsidiaries FSP Investments LLC and FSP Property
Management LLC (collectively, “FSP”). The Company expects to continue to have related party transactions with FSP in
the form of management fees paid to FSP to manage the Company on behalf of our stockholders. FSP Property Management LLC currently
provides the Company with asset management and financial reporting services. The asset management agreement between the Company
and FSP Property Management LLC requires the Company to pay FSP Property Management LLC a monthly fee equal to one percent (1%)
of the gross revenues of the Property. The asset management agreement between the Company and FSP Property Management LLC may be
terminated by either party without cause at any time, upon at least thirty (30) days written notice, effective at the end of the
notice period. For the years ended December 31, 2010 and 2009, management fees paid were $161,000 and $162,000, respectively.



Franklin Street is the sole holder of the Company’s
one share of Common Stock that is issued and outstanding. Subsequent to the completion of the private placement of the Preferred
Stock in January 2007, Franklin Street has not been entitled to share in any earnings or any dividend as a result of its ownership
of the Common Stock of the Company.



F-13





FSP 50
South Tenth Street Corp.

Notes to Consolidated Financial Statements



7.     Commitments and Contingencies



The Company, as lessor, has minimum future rentals due under non-cancelable
operating leases as follows:



|               |  | Year Ending  |  |                  
|-------------- |  | ------------ |  | -----------------
|(in thousands) |  | December 31, |  | Amount           
|               |  | 2011         |  | $           8,957
|               |  | 2012         |  | 7,490            
|               |  | 2013         |  | 7,421            
|               |  | 2014         |  | 3,580            
|               |  | 2015         |  | 1,547            
|               |  | Thereafter   |  | 2,441            
|               |  |              |  |                  
|               |  |              |  | $         31,436 



In addition, the lessees are liable for real
estate taxes and certain operating expenses of the Property.



Upon acquiring the commercial rental property
on November 8, 2006, the Company was assigned the lease agreements between the seller of the Property and the existing tenants.



8.     Segment Reporting



The Company operates in one industry segment
– real estate ownership of commercial property. As of December 31, 2010 and 2009, the Company owned and operated a twelve-story
multi-tenant office and retail building in that one segment.



9.     Accounts Payable and Accrued
Expenses



Accounts payable and accrued expenses consist of the components
shown below:



|                                            |  | December 31,
|------------------------------------------- |  | ------------
|(in thousands)                              |  | 2010        
|                                            |  |             
|Deferred rental income                      |  | $           
|Accrued operating expenses                  |  |             
|Due to tenants                              |  |             
|Accounts payable and other accrued expenses |  |             
|Total                                       |  | $           



10.     Subsequent
Event



On January 26, 2011, the Board of Directors of the Company declared
a cash distribution of $1,225,000 payable on March 1, 2011 to stockholders of record on February 9, 2011.



F-14





SCHEDULE III



FSP 50 South Tenth Street Corp.

Real Estate and Accumulated Depreciation

December 31, 2010

(in thousands)





|                                       |              | Initial Cost   |                                     | Historical Costs                                       |  |        
|-------------------------------------- | ------------ | -------------- | ----------------------------------- | ------------------------------------------------------ |  | -------
|Description                            | Encumbrances | Land           | Buildings
Improvementsand Equipment | Costs
Capitalized
(Disposals)
Subsequent toAcquisition |  | Land   
|                                       |              | (in thousands) |                                     |                                                       
|50 South Tenth Street, Minneapolis, MN | $76,200      | $21,974        | $97,321                             | $617                                                   |  | $21,974



(1)The
aggregate cost for Federal Income Tax purposes is $128,074.



F-15





FSP 50 South Tenth Street Corp.



The following table summarizes the changes in the Company’s
real estate investments and accumulated depreciation:



|                                  |  | December 31, |         | December 31,
|--------------------------------- |  | ------------ | ------- | ------------
|(in thousands)                    |  | 2010         |         | 2009        
|                                  |  |              |         |             
|                                  |  |              |         |             
|Real estate investments, at cost: |  |              |         |             
|Balance, beginning of year        |  | $            | 119,469 |             
|Improvements                      |  |              | 443     |             
|                                  |  |              |         |             
|Balance, end of year              |  | $            | 119,912 |             
|                                  |  |              |         |             
|Accumulated depreciation:         |  |              |         |             
|Balance, beginning of year        |  | $            | 7,941   |             
|Depreciation                      |  |              | 2,573   |             
|                                  |  |              |         |             
|Balance, end of year              |  | $            | 10,514  |             







F-16