<PAGE>

                       SECURITIES AND EXCHANGE COMMISSION

                             Washington, D.C. 20549

                                   FORM 10-KSB

              Annual Report Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934

                                                                 Commission File
For the year ended December 31, 1999                           No.    0-9684
                   -----------------                               -------------

                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP
--------------------------------------------------------------------------------
        (Exact name of small business issuer as specified in its charter)

          Massachusetts                                       04-2693546
---------------------------------                       ------------------------
 (State or other jurisdiction of                         (I.R.S.  Employer
   incorporation or organization)                        Identification No.)

         5 Cambridge Center, Cambridge, Massachusetts              02142
                                       ---------------           ---------
           (Address of principal executive offices)              (Zip Code)

         Registrant's telephone number including area code (617)234-3000
                                                           -------------

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

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

                      Units of Limited Partnership Interest
                      -------------------------------------
                                (Title of Class)

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 if disclosure of delinquent filers pursuant to Item 405
of Regulation S-B 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-KSB or any amendment to
this Form 10-KSB. [ ]

Registrant's revenues for its most recent fiscal year were $1,619,000.

No market for the Limited Partnership Units exists and therefore, a market value
for such Units cannot be determined.

                       DOCUMENTS INCORPORATED BY REFERENCE

                                      None


<PAGE>

                                     PART I
                                     ------

Item 1.  Description of Business.
------   -----------------------

      Winthrop Partners 80 Limited Partnership (the "Partnership"), a limited
partnership, was organized under the Uniform Limited Partnership Act of the
Commonwealth of Massachusetts on February 5, 1980, for the purpose of owning and
leasing commercial and industrial real properties. The Partnership was initially
capitalized with contributions of $1,000 from each of the two General Partners
and $5,000 from the Initial Limited Partner. In February, 1981, the Partnership
sold pursuant to a Registration Statement filed with the Securities and Exchange
Commission 45,636 units of limited partnership interest ("Units") at a purchase
price of $500 per Unit representing capital contributions from Limited Partners
of $22,818,000.

      The Partnership's General Partners are One Winthrop Properties, Inc., a
Massachusetts corporation (the "Managing General Partner"), and
Linnaeus-Hampshire Realty Limited Partnership (formerly known as
Linnaeus-Hampshire Realty Company), a Massachusetts limited partnership (the
"Associate General Partner"). One Winthrop Properties, Inc. is a wholly-owned
subsidiary of First Winthrop Corporation ("First Winthrop"), a Delaware
corporation, which is wholly owned by Winthrop Financial Associates, A Limited
Partnership ("WFA"), a Maryland limited partnership.

      The Partnership's only business is owning and leasing improved real
estate.

      In December 1981, the Partnership completed its investment of the net
proceeds of the Limited Partners' capital contributions, other than
approximately $200,000 originally set aside as reserves, in 18 real properties.
The Partnership's reserves at December 31, 1999, net of accounts payable,
accrued expenses and distributions payable to partners is approximately
$1,210,000 which is invested in money market instruments. Thirteen properties
have been sold: one in 1989, two in 1991, two in 1992, two in 1993, one in
January 1996, one in August 1997, one in March 1998 and three in 1999. See Item
2, "Description of Properties" for a description of the Partnership's remaining
properties. In addition, the Partnership acquired in 1996 the vacant parcel of
land adjacent to its Mt. Pleasant property. See "Acquisitions and Dispositions"
below. Many of the properties are located in areas with depressed economies,
making potential purchasers concerned about a possible rental reduction when
existing leases expire. Rental income will be affected by the

                                       2
<PAGE>

terms of any new leases, any tenant improvement and leasing costs associated
with renewing leases with existing tenants or signing leases with new tenants,
the loss of rent during any period when a property is not under lease and the
loss of rent after a property is sold. Pursuant to the terms of the Partnership
Agreement, so long as limited partners have received aggregate distributions
from inception equal to 8% of their capital contributions, the general partner
is entitled to receive distributions in an amount equal to 8% of the total
distributions paid to the limited partners. Distributions of sale proceeds will
be made as a partial return of capital. Pursuant to the Partnership's
partnership agreement, sale proceeds are distributed 100% to limited partners
until they have received their $500 per unit original capital contribution. At
December 31, 1999, limited partners had received a return of capital equal to
$198.40. The general partners' 8% share of sale proceeds would be paid
subsequently.

Property Matters

      Wal-Mart, Bowling Green, Kentucky. On June 16, 1999, the Partnership sold
its Bowling Green, Kentucky property for $1,757,000 (net of closing costs of
$143,000). The Partnership had to spend $152,000 in improvements before the
sale. Since the carrying value of the property was $1,237,000, the Partnership
realized a gain of $520,000. The Partnership is negotiating with Wal-Mart for
the settlement of insurance proceeds for damages sustained as a result of a
hailstorm in April 1998. Insurance proceeds are expected to be between $500,000
and $750,000.

      Dairy Mart, Ashtabula, Ohio - The lease with Dairy Mart expired on July 1,
1995. The property, which remained vacant, was sold on July 23, 1999 for $34,000
(net of closing costs of $6,000). Since the carrying value of the property was
written down to zero, the Partnership realized a gain of $34,000.

      Dairy Mart, Bolivar, Ohio - The lease with respect to this property
expired on December 31, 1998. The property, which remained vacant, was sold on
October 27, 1999 for approximately $137,000 (net of approximately $11,000 in
closing costs). Since the carrying value of the property was $39,000, the
Partnership will realize a gain of approximately $98,000 during the fourth
quarter of 1999.

      Dairy Mart, Creston, Ohio - In August 1997, the Partnership sold this
property to the tenant for $85,000 resulting in net proceeds, after closing
costs, to the Partnership of approximately $80,000. The Partnership recognized a
gain of $46,000 from this sale. The Partnership's original investment in

                                       3
<PAGE>


this property represented less than 1% of the initial offering proceeds.

      Dairy Mart, Royal Oak, Michigan - The Partnership sold this property to
the tenant on March 6, 1998 for a purchase price of $200,000. The Partnership
received net proceeds, after closing costs, of $194,000 resulting in a gain of
$131,000. The net proceeds were distributed during the second quarter of 1998.

      Motorola, Inc., Mt. Pleasant, IA. During the second half of 1996, the
Partnership acquired the parcel of land immediately adjacent to this property
for $25,000. The lease with Motorola was scheduled to expire November 30, 1999.
Motorola, however, elected to extend the lease for an additional one year term
at the then current rent. The Managing General Partner believes that the
purchase of the adjacent property will have a positive effect on the value of
the property.

      Hobby Lobby Creative Center, Victoria, TX. During January 1998, the
Partnership leased approximately 60,000 square feet of the 96,000 square feet at
this property to Hobby Lobby Creative Center. This new lease is scheduled to
expire May 2008 with the tenant having two renewal options of five years each.
Wal-Mart, whose lease was scheduled to expire in December 2000, vacated the
property but continued to pay rent until June 1, 1998. In addition, the
Partnership was paid a termination fee in the amount of $200,000.

      Toys R Us, Livingston, NJ and Beaumont, TX. The original lease term at
both of these properties was scheduled to expire on January 31, 2001. The tenant
has exercised its option to renew these lease terms for an additional five year
term (January 31, 2006).

Employees

      The Partnership does not have any employees. Services are performed for
the Partnership by its General Partners, and by agents retained by the General
Partners, including an affiliate of the General Partners, Winthrop Management.

                                       4
<PAGE>

Item 2.     Description of Properties.
------      -------------------------

      A description of the Partnership's remaining properties is as follows. All
of the Partnership's remaining properties are owned in fee.

                                      Total Cost   Original
     Tenant                Date of      of the     Portfolio      Building/
Property/Location          Purchase   Property(1)  Percentage(2)  Land (3)
-----------------          --------   -----------  ------------   -----------

Toys "R" Us, Inc.
 Livingston, NJ            11/19/80     2,127,950     10.7        43,000/5.0
 Beaumont, TX              11/19/80     2,234,050     11.3        43,000/4.5
Motorola, Inc.
 Mt. Pleasant, IA          12/24/80       982,617     5           35,700/3.0
Duckwall-Alco Stores, Inc. 12/24/80       972,007     5           35,700/2.0
 Nebraska City, NE
Hobby-Lobby
 Creative Center
 Victoria, TX              12/30/80     3,121,436    15           96,498/7.8


(1)   Includes acquisition fees and expenses.
(2)   Represents the percentage of original cash invested in the individual
      property of the total cash invested in all properties.
(3)   Building size is in square feet, land size is in acres.

      The Partnership owns the fee interest in each of these properties free of
any mortgages. All of the properties are commercial or industrial in nature and
are triple net leased to a single tenant. Each of the tenants, other than
Hobby-Lobby Creative Center, is a public company or a subsidiary of a public
company. The tenants under the leases have exclusive control over the day-to-day
business operations conducted at the Properties as well as decisions with
respect to the initiation of any development or renovations at the Properties.
The Partnership has limited approval rights over any such renovation programs
proposed by the tenants. The Partnership has no responsibility for any
maintenance, repairs or improvements associated with these Properties other than
the Victoria, Texas property, at which the Partnership is responsible for all
exterior repairs. In addition, the tenants are responsible for all insurance
requirements and the payment of real estate taxes directly to the taxing
authorities other than Hobby-Lobby which is required to pay to the Partnership
additional rent to cover insurance, real estate taxes, and common area
maintenance charges. . The Partnership believes that each of the Properties is
adequately covered by insurance.

      Each retail tenant is subject to competition from other companies offering
similar products in the locations of the property leased by such tenant. In
addition, the Partnership anticipates that it would be subject to significant
competition in attracting tenants upon the expiration or termination of any

                                       5
<PAGE>

of the leases of its properties. The Partnership has no control over the
tenants' responses to competitive conditions impacting the businesses operated
by the tenants at each of the properties.

      Tenants with 1999 rental payments,  including  percentage  rents, of 10%
or more of the Partnership's  total rental revenue,  are as follows:  Toys "R"
Us, Inc. in Livingston,  New Jersey,  25%;  Motorola facility in Mt. Pleasant,
Iowa, 12%;  Duckwall-Akco Store in Nebraska City, Nebraska,  10%; Toys "R" Us,
Inc. in Beaumont,  Texas,  21%; and  Hobby-Lobby  Creative Center in Victoria,
Texas, 25%.

      The following table sets forth the tenant, business conducted by the
tenant, expiration date of the lease term, renewal options and the 1999 annual
base rent for the leases at the Partnership's remaining properties:

Tenant                    Business of  Lease          Renewal     1999 Annual
Property/Location         Tenant       Expiration     Option (1)  Base Rent
-----------------         -----------  ----------     ----------  ------------

Toys "R" Us, Inc.         Retail Toy   1-31-2006(4)   4 - 7yr.    $214,000(3)
Livingston, NJ            Store

Toys "R" Us, Inc.         Retail Toy   1-31-2006(4)   4 - 5yr.    $224,700
Beaumont, TX              Store

Motorola, Inc. Mt.        Retail       11-30-2000     1- 1yr.     $132,509
Pleasant, IA              Dept. Store

Duckwall-Alco Stores,     Retail       12-22-2000     -           $109,200(2)
Inc. Nebraska City, NE    Dept. Store

Hobby Lobby Creative      Hobby Store  5-31-2008      2 - 5yr.    $102,883
Center, Victoria, TX

---------------------
(1)   The first number represents the number of renewal options. The second
      number represents the length of each option.
(2)   Additional percentage rent of $3,542, representing a percentage of
      store
      sales was received in 1999.
(3)   Additional percentage rent of $56,160, representing a percentage of store
      sales was received in 1999.
(4)   Tenant exercised renewal option on February 3, 2000.

                                       6
<PAGE>

      Set forth below is a table showing the gross carrying value and
accumulated depreciation and federal tax basis of each of the Partnership's
properties as of December 31, 1999:

                    Gross
                   Carrying   Accumulated                          Federal
Property            Value(1)  Depreciation(1)  Rate     Method    Tax Basis
--------            -----     ------------     ----     ------    ---------

Livingston, NJ      595,826      -              -        -           955,347

Beaumont, TX        647,874      -              -        -         1,087,540

Mt. Pleasant, IA    524,887      -           5/40 yr.  S/L           312,495

Nebraska            580,000      -           5/40 yr.  S/L           303,922
   City, NE

Victoria, TX       $2,143,297    -             -        -           1,110,593

(1)   As accounted for under Statement of Financial Accounting Standards No.
      13.

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

      The Partnership is not a party, nor are any of its properties subject, to
any material pending legal proceedings.

Item 4.     Submission of matters to a vote of securities holders.
------      -----------------------------------------------------

      No matters were submitted to a vote of security holders.


                                       7
<PAGE>

                                     PART II
                                     -------

Item 5.  Market Price for the Partnership's Common Equity and
         ----------------------------------------------------
         Related Stockholder Matters.
         ---------------------------

      There is no established public market for the Units. Trading in the Units
is sporadic and occurs solely through private transactions.

      As of March 1, 2000, there were 1,550 holders of 45,646 outstanding Units.

      The Partnership's partnership agreement requires that any Cash Available
for Distribution (as defined therein) be distributed quarterly to the Partners
in specified proportions and priorities. There are no restrictions on the
Partnership's present or future ability to make distributions of Cash Available
for Distribution. During the years ended December 31, 1999 and 1998, the
Partnership has made the following cash distributions with respect to the Units
to holders thereof as of the dates set forth below in the amounts set forth
opposite such dates:

      Distribution with                   Amount of Distribution
      Respect to Quarter Ended            Per Unit
      ------------------------            --------

                                                1999              1998
                                                ----              ----

      March 31                                      --            $14.11
      June 30                                   $ 5.58              6.43
      September 30                               41.25              6.41
      December 31                                 9.96              6.79

      Pursuant to a tender offer commenced on August 23, 1999, an affiliate of
the Managing General Partner acquired, for a purchase price of $160 per unit,
approximately 18.25% of the total limited partnership units of the Partnership
(8,328.48 units).

      Over the past few years many companies have begun making "mini-tenders"
(offers to purchase an aggregate of less than 5% of the total outstanding units)
for limited partnership interests in the Partnership. Pursuant to the rules of
the Securities and Exchange Commission, when a tender offer is commenced for
Units the Partnership is required to provide limited partners with a statement
setting forth whether it believes limited partners should tender or whether it
is remaining neutral with respect to the offer. Unfortunately, the rules of the
Securities and Exchange Commission do not require that the bidders in certain
tender offers provide the Partnership with a copy of their offer. As a result,
the Managing General Partner often does not become

                                       8
<PAGE>

aware of such offers until shortly before they are scheduled to expire or even
after they have expired. Accordingly, the Managing General Partner does not have
sufficient time to advise you of its position on the tender. In this regard,
please be advised that pursuant to the discretionary right granted to the
Managing General Partner of your partnership in the Partnership Agreement to
reject any transfers of units, the Managing General Partner will not permit the
transfer of any Unit in connection with a tender offer unless: (i) the
Partnership is provided with a copy of the bidder's offering materials,
including amendments thereto, simultaneously with their distribution to the
limited partners; (ii) the offer provides for withdrawal rights at any time
prior to the expiration date of the offer and, if payment is not made by the
bidder within 60 days of the date of the offer, after such 60 day period; and
(iii) the offer must be open for at least 20 business days and, if a material
change is made to the offer, for at least 10 business days following such
change.


                                       9
<PAGE>

Item 6.  Management's Discussion and Analysis or Plan of
         -----------------------------------------------
         Operation
         ---------

      The matters discussed in this Form 10-KSB contain certain forward-looking
statements and involve risks and uncertainties (including changing market
conditions, competitive and regulatory matters, etc.) detailed in the
disclosures contained in this Form 10-KSB and the other filings with the
Securities and Exchange Commission made by the Registrant from time to time. The
discussion of the Registrant's liquidity, capital resources and results of
operations, including forward-looking statements pertaining to such matters,
does not take into account the effects of any changes to the Registrant's
operations. Accordingly, actual results could differ materially from those
projected in the forward-looking statements as a result of a number of factors,
including those identified herein.

      Liquidity and Capital Resources

      Each of the Partnership's remaining five properties is leased to a single
tenant pursuant to net leases with remaining lease terms, subject to extensions,
ranging between eleven months and eight years. The Partnership receives rental
income from its properties which is its primary source of liquidity. Pursuant to
the terms of the leases, the tenants are responsible for substantially all of
the operating expenses with respect to the properties including, maintenance,
capital improvements, insurance and taxes (except for the Victoria, Texas
property where the tenant is responsible only for its proportionate share of
expenses other than capital improvements). Two of the Partnership's properties,
representing approximately 24% of minimum rental receipts anticipated during
2000, have leases which expire on November 30, 2000 and December 22, 2000. If a
tenant fails to exercise its renewal option, exercises its option to terminate
its lease early or does not renew at the expiration of the lease term, the
Partnership will be required to either sell the properties or procure new
tenants. If the Partnership attempts to procure new tenants, it will be
competing for new tenants in the then current rental markets, which may not be
able to support terms as favorable as those contained in the original lease
options.

      The Partnership's Bowling Green, Kentucky property was sold to an
unaffiliated third party on June 16, 1999 for $1,757,000 (net of closing costs
of $143,000). The Partnership had to spend $152,000 in improvements before the
sale. Since the carrying value of the property was $1,237,000, the Partnership
realized a gain of $520,000. The Partnership is negotiating with Wal-Mart for
the settlement of insurance proceeds for damages sustained as a result of a
hailstorm in April 1998. Insurance proceeds are expected to be between $500,000
and $750,000.

                                       10
<PAGE>

      The Partnership's Ashtabula, Ohio property was sold to an unaffiliated
third party on July 23, 1999 for $34,000 (net of closing costs of $6,000). Since
the carrying value of the property was written down to zero, the Partnership
realized a gain of $34,000.

      On October 27, 1999, the Partnership sold its property located in Bolivar,
Ohio to an unaffiliated third party for $137,000 (net of closing costs of
$11,000), since the carrying value of the property was $39,000, the Partnership
realized a gain of $98,000.

      During January 1999, the Partnership leased approximately 60,000 square
feet of the 96,000 square foot Victoria, Texas property to Hobby Lobby Creative
Center pursuant to a lease which expires May 2008, with two renewal options of
five years each. The previous tenant's lease (Wal-Mart) was to expire in
December 2000, however, on January 30, 1999, the Partnership signed a lease
termination agreement with the previous tenant whereby the previous tenant
agreed to make certain improvements to the property, pay rent through June 1,
1999 and pay a termination fee in the amount of $200,000. The new lease with
Hobby Lobby provides for a higher rental rate, per square foot than Wal-Mart.

      The level of liquidity based on cash and cash equivalents experienced a
$192,000 increase at December 31, 1999 as compared to December 31, 1998. The
increase was due to $1,901,000 provided by investing activities and $738,000
provided by operating activities, which was partially offset by $2,447,000 of
cash used for partner distributions. The investing activities consisted of net
sale proceeds of $1,927,000 and minimum lease payments (net of interest income)
of $220,000 which was partially offset by real estate improvements of $246,000.
At December 31, 1999, the Partnership had $1,953,000 in cash reserves, which has
been invested primarily in money market mutual funds.

      The Partnership requires cash primarily to pay management fees and general
and administrative expenses. In addition, the Partnership is responsible for
operating expenses, such as real estate taxes, insurance and utility expenses
associated with the vacant properties (which were sold during the year) and a
portion of expenses for the Victoria, Texas property and would be responsible
for similar expenses if other properties were to become vacant upon the
expiration of leases. The Partnership's rental and interest income was
sufficient for the year ended December 31, 1999, and is expected to be
sufficient until expiration of the leases, to pay all of the Partnership's

                                       11
<PAGE>

operating expenses as well as to provide for cash distributions to the partners
from operations. As of December 31, 1999, Partnership distributions (paid or
accrued) aggregated $2,592,000 ($56.78 per unit) to its limited partners, which
included approximately $1,927,000 of proceeds from the sale of the Partnership's
Bowling Green, Kentucky and Ashtabula and Bolivar, Ohio properties.

      Due to the net and long-term nature of the original leases, inflation and
changing prices have not significantly affected the Partnership's revenues and
net income. As tenant leases expire, the Partnership expects that inflation and
changing prices will affect the Partnership's revenues. The Motorola lease which
expired in November 1999, was extended for another year until November 2000 at
the same rental rate. The Toys `R' Us Inc.'s leases for Livingston, New Jersey
and Beaumont, Texas were extended for five years at the same rental rate and
will mature on January 31, 2006.

      The Partnership maintains cash reserves to enable it to make potential
capital improvements required in connection with the re-letting of the
properties. The Partnership invests its working capital reserves in money market
mutual funds.

      During 1999, an affiliate of the general partner acquired, for a purchase
price of $160 per unit, approximately 19% of the total limited partnership units
of the Partnership (8,851.64 units).

      Results of Operations

      Net income increased by $46,000 for the year ended December 31, 1999, as
compared to 1998, due to an increase in revenues of $142,000, which more than
offset an increase in expenses of $96,000.

      Revenues increased due to the $652,000 gain on sales of the Bowling Green,
Kentucky property, Ashtabula, Ohio property and Bolivar, Ohio property during
1999, as compared to a $131,000 gain on the sale of the Royal Oak, Michigan
property during the year ended December 31, 1998. With respect to the remaining
properties, rental income increased by approximately $151,000 and interest
income on real estate leases declined by $106,000, primarily due to the
Victoria, Texas property being converted to an operating lease. In addition,
other income decreased by

                                       12
<PAGE>


$198,000 and interest income on short term investments increased by $24,000.

      The increase in expense was attributable to increases in depreciation,
amortization and operating expenses. Depreciation and amortization expense
increased by $29,000 primarily as a result of reclassifying the new lease at the
Victoria, Texas property as an operating lease from a financing lease. Operating
expenses increased by approximately $66,000, due to expenses paid for the vacant
properties, as well as, a portion of the Victoria, Texas property.

                                       13
<PAGE>

Item 7.  Financial Statements
         --------------------


                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                              FINANCIAL STATEMENTS

                          YEAR ENDED DECEMBER 31, 1999

                                      INDEX

                                                                           Page
                                                                           -----

Independent Auditors' Report...............................................F - 2

Financial Statements:

Balance Sheets as of December 31, 1999 and 1998............................F - 3

Statements of Income for the Years Ended
   December 31, 1999 and 1998..............................................F - 4

Statements of Partners' Capital for the Years Ended
   December 31, 1999 and 1998..............................................F - 5

Statements of Cash Flows for the Years Ended
   December 31, 1999 and 1998..............................................F - 6

Notes to Financial Statements..............................................F - 7





                                      F - 1


<PAGE>



                          Independent Auditors' Report
                          ----------------------------

To the Partners
Winthrop Partners 80 Limited Partnership

We have audited the accompanying balance sheets of Winthrop Partners 80 Limited
Partnership (a Massachusetts limited partnership) as of December 31, 1999 and
1998, and the related statements of income, partners' capital and cash flows for
the years then ended. These financial statements are the responsibility of the
Partnership's management. Our responsibility is to express an opinion on these
financial statements based on our audits.

We conducted our audits in accordance with generally accepted auditing
standards. Those standards require that we plan and perform the audit to obtain
reasonable assurance about whether the financial statements are free of material
misstatement. An audit includes examining, on a test basis, evidence supporting
the amounts and disclosures in the 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 financial statements referred to above present fairly, in
all material respects, the financial position of Winthrop Partners 80 Limited
Partnership as of December 31, 1999 and 1998, and the results of its operations
and its cash flows for the years then ended, in conformity with generally
accepted accounting principles.

                                                    /s/Imowitz Koenig & Co., LLP


New York, New York
February 14, 2000

                                      F - 2


<PAGE>

                                   WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                                                BALANCE SHEETS
                                                --------------
                                       (In Thousands, Except Unit Data)
<TABLE>
<CAPTION>

                                                                                    DECEMBER 31,
                                                                        -------------------------------------

                                                                              1999                1998
                                                                        -----------------   -----------------

ASSETS
<S>                                                                    <C>                 <C>
Real Estate Leased to Others:

Accounted for under the operating method,
      at cost, net of accumulated depreciation of
      $592 (1999) and $506 (1998)                                       $          3,914    $          4,456
Accounted for under the operating method, at cost,
      net of accumulated depreciation of $85 and held for sale                        -                   39
Accounted for under the financing method                                           1,139               1,975
                                                                        -----------------   -----------------

                                                                                   5,053               6,470

Other Assets:

Cash and cash equivalents                                                          1,953               1,761
Other assets                                                                          70                  69
                                                                        -----------------   -----------------

          Total Assets                                                  $          7,076    $          8,300
                                                                        =================   =================

LIABILITIES AND PARTNERS' CAPITAL

Liabilities:

Accounts payable and accrued expenses                                   $             46    $            146
Distributions payable to partners                                                    697                 310
                                                                        -----------------   -----------------

          Total Liabilities                                                          743                 456
                                                                        -----------------   -----------------

Partners' Capital:

Limited Partners -
   Units of Limited Partnership Interest,
   $500 stated value per Unit; authorized - 50,010
   Units; issued and outstanding - 45,646 Units                                    6,925               8,254
General Partners' Deficit                                                           (592)               (410)
                                                                        -----------------   -----------------

          Total Partners' Capital                                                  6,333               7,844
                                                                        -----------------   -----------------

          Total Liabilities and Partners' Capital                       $          7,076    $          8,300
                                                                        =================   =================
</TABLE>


                                      See notes to financial statements.

                                                    F - 3

<PAGE>
                                WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                                          STATEMENTS OF INCOME
                                          --------------------
                                    (In Thousands, Except Unit Data)
<TABLE>
<CAPTION>

                                                                       YEARS ENDED DECEMBER 31,
                                                                 --------------------------------------

                                                                       1999                1998
                                                                 -----------------   ------------------
<S>                                                              <C>                 <C>
Income:
Rental income from real estate leases accounted
     for under the operating method                              $            713    $             660
Interest on short-term investments                                            113                   89
Interest income on real estate leases accounted
     for under the financing method                                           139                  397
Gain on sale of property                                                      652                  131
Other income                                                                    2                  200
                                                                 -----------------   ------------------

        Total income                                                        1,619                1,477
                                                                 -----------------   ------------------

Expenses:
Depreciation and amortization                                                  92                   63
Management fees                                                                15                   21
Operating Expenses                                                             88                   22
General and administrative                                                    101                   94
                                                                 -----------------   ------------------

        Total expenses                                                        296                  200
                                                                 -----------------   ------------------

Net income                                                       $          1,323    $           1,277
                                                                 =================   ==================

Net income allocated to general partners                         $             60    $              93
                                                                 =================   ==================

Net income allocated to limited partners                         $          1,263    $           1,184
                                                                 =================   ==================

Net income per Unit of Limited Partnership Interest              $          27.67    $           25.94
                                                                 =================   ==================

Distributions per Unit of Limited Partnership Interest           $          56.78    $           33.74
                                                                 =================   ==================
</TABLE>




                                   See notes to financial statements.

                                                  F - 4

<PAGE>
                                 WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                                      STATEMENTS OF PARTNERS' CAPITAL
                                      -------------------------------
                                  YEARS ENDED DECEMBER 31, 1999 AND 1998
                                  --------------------------------------
                                     (In Thousands, Except Unit Data)
<TABLE>
<CAPTION>

                                         Units of
                                         Limited          General          Limited
                                       Partnership       Partners'        Partners'           Total
                                         Interest         Deficit          Capital           Capital
                                      --------------- ----------------  ---------------  ----------------

<S>                                   <C>             <C>               <C>              <C>
Balance - January 1, 1998                     45,646  $          (503)  $        8,610   $         8,107

   Distributions                                                    -           (1,540)           (1,540)
   Net income                                                      93            1,184             1,277
                                      --------------- ----------------  ---------------  ----------------

Balance - December 31, 1998                   45,646             (410)           8,254             7,844

   Distributions                                                 (242)          (2,592)           (2,834)
   Net income                                                      60            1,263             1,323
                                      --------------- ----------------  ---------------  ----------------

Balance - December 31, 1999                   45,646  $          (592)  $        6,925   $         6,333
                                      =============== ================  ===============  ================
</TABLE>



















                                    See notes to financial statements.

                                                   F - 5
<PAGE>
                                   WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                                           STATEMENTS OF CASH FLOWS
                                           ------------------------
                                                (In Thousands)
<TABLE>
<CAPTION>


                                                                              YEARS ENDED DECEMBER 31,
                                                                        -------------------------------------

                                                                               1999                1998
                                                                        -----------------   -----------------

CASH FLOWS FROM OPERATING ACTIVITIES:
<S>                                                                     <C>                 <C>
Net income                                                              $          1,323    $          1,277
Adjustments to reconcile net income to net cash provided
  by operating activities:
      Depreciation                                                                    87                  59
      Amortization                                                                     5                   4
      Gain on sale of property                                                      (652)               (131)

Changes in assets and liabilities:
      Increase in other assets                                                        (5)                (58)
      (Decrease) increase in accounts payable and
          accrued expenses                                                           (20)                  3
                                                                        -----------------   -----------------

      Net cash provided by operating activities                                      738               1,154
                                                                        -----------------   -----------------

CASH FLOWS FROM INVESTING ACTIVITIES:

      Minimum lease payments received, net of interest income
         earned, on leases accounted for under the financing method                  220                 334
      Proceeds from sale of property                                               1,927                 194
      Additions to real estate                                                      (246)                (80)
                                                                        -----------------   -----------------

      Net cash provided by investing activities                                    1,901                 448
                                                                        -----------------   -----------------

CASH FLOWS FROM FINANCING ACTIVITIES:

      Cash distributions                                                          (2,447)             (1,382)
                                                                        -----------------   -----------------

      Cash used in financing activities                                           (2,447)             (1,382)
                                                                        -----------------   -----------------

Net increase in cash and cash equivalents                                            192                 220

Cash and Cash Equivalents, Beginning of Year                                       1,761               1,541
                                                                        -----------------   -----------------

Cash and Cash Equivalents, End of Year                                  $          1,953    $          1,761
                                                                        =================   =================

Supplemental Disclosure of Non-Cash Financing and Investing
      Activities -

Distributions declared not paid as of December 31                       $            697    $            310
                                                                        =================   =================

Additions to real estate                                                $              -    $             80
                                                                        =================   =================
</TABLE>

                                      See notes to financial statements.

                                                    F - 6
<PAGE>


                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                          NOTES TO FINANCIAL STATEMENTS
                          -----------------------------
                     YEARS ENDED DECEMBER 31, 1999 AND 1998
                     --------------------------------------

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES
   -----------------------------------------------------------

   Organization

   Winthrop Partners 80 Limited Partnership (the "Partnership") was organized
   under the Uniform Limited Partnership Act of the Commonwealth of
   Massachusetts on February 5, 1980 for the purpose of owning and leasing
   commercial and industrial real properties. The Partnership owns and leases
   five properties, two of which are located in Texas and one each in Iowa,
   Nebraska and New Jersey. All the properties are leased to single tenants
   under net lease agreements.

   Use of Estimates

   The preparation of financial statements in conformity with generally accepted
   accounting principles requires management to make estimates and assumptions
   that affect the amounts reported in the financial statements and accompanying
   notes. Such estimates that are particularly susceptible to change relate to
   the Partnership's estimate of the fair value of real estate. Actual results
   could differ from those estimates.

   Leases

   The Partnership leases its real properties and accounts for such leases in
   accordance with the provisions of Statement of Financial Accounting Standards
   No. 13, "Accounting for Leases", as amended. This statement sets forth
   specific criteria for determining whether a lease should be accounted for as
   a financing lease or an operating lease.

   (a)   Financing Method

      Under this method, minimum lease payments to be received plus the
      estimated value of the property at the end of the lease are considered to
      be the Partnership's gross investment in the lease. Unearned income,
      representing the difference between gross investment and actual cost of
      the leased property, is amortized over the lease term using the interest
      rate implicit in the lease to provide a level rate of return over the
      lease term.

   (b)   Operating Method

      Under this method, revenue is recognized as rentals become due, which does
      not materially differ from the straight-line method. Expenses (including
      depreciation) are charged to operations as incurred.

   Percentage Rent

   The Partnership has entered into several leases that provide for a minimum
   annual rent plus additional rent based on percentages of sales at the
   properties ("percentage rent"). These percentage rents are recorded on a cash
   basis. For the years ended December 31, 1999 and 1998, the Partnership
   received percentage rent totaling approximately $60,000 and $78,000,
   respectively.

                                      F - 7


<PAGE>



                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                          NOTES TO FINANCIAL STATEMENTS
                          -----------------------------
                     YEARS ENDED DECEMBER 31, 1999 AND 1998
                     --------------------------------------
                                   (continued)
                                   -----------

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)
   -----------------------------------------------------------------------

   Real Estate

   Real estate is carried at cost, adjusted for depreciation and impairment of
   value. In accordance with Statement of Financial Accounting Standards
   ("SFAS") No. 121, "Accounting for the Impairment of Long-Lived Assets and for
   Long-Lived Assets to Be Disposed Of", the Partnership records impairment
   losses for long-lived assets used in operations when indicators of impairment
   are present and the undiscounted cash flows are not sufficient to recover the
   asset's carrying amount. The impairment loss is measured by comparing the
   fair value of the asset to its carrying amount.

   Depreciation

   Component depreciation on real estate leased to others, accounted for under
   the operating method, is computed using the straight-line method over the
   estimated useful life of each class of asset, which ranges from 5 to 40
   years. The cost of the properties represents the purchase price of the
   properties plus acquisition and closing costs, or, to the extent that the
   property had previously been accounted for under the financing method, the
   depreciable base is the fair market value at the date of implementation of
   operating lease accounting.

   Deferred Costs

   Deferred leasing costs are amortized on a straight-line basis over the life
   of the respective lease. Accumulated amortization totaled $9,000 and $4,000
   at December 31, 1999 and 1998, respectively. Deferred leasing costs are
   included in other assets.

   Cash and Cash Equivalents

   The Partnership considers all highly liquid investments with an original
   maturity of three months or less at the time of purchase to be cash
   equivalents.

   Fair Value of Financial Instruments

   The carrying amount of cash and cash equivalents approximates its fair value
   due to the short term nature of such instruments.

   Distributions to Partners

   The Partnership's distributions (paid or accrued) aggregated $2,592,000
   ($56.78 per Unit) and $1,540,000 ($33.74 per Unit) to its limited partners
   for the years ended December 31, 1999 and 1998, respectively. Since the
   limited partners priority distributions were met, the general partners are
   entitled to a distribution of $242,000. The cash distribution due partners
   for the three months ended December 31, 1999 and 1998 is recorded in the
   accompanying financial statements as a liability and a reduction of partner's
   capital.

                                      F - 8


<PAGE>



                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                          NOTES TO FINANCIAL STATEMENTS
                          -----------------------------
                     YEARS ENDED DECEMBER 31, 1999 AND 1998
                     --------------------------------------
                                   (continued)
                                   -----------

1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Continued)
   -----------------------------------------------------------------------

   Net Income Per Limited Partnership Unit

   Net income per limited partnership unit is computed by dividing net income
   allocated to the limited partners by the 45,646 units outstanding.

   Income Taxes

   Taxable income or loss of the Partnership is reported in the income tax
   returns of its partners. Accordingly, no provision for income taxes is made
   in the financial statements of the Partnership.

   Concentration of Credit Risk

   Principally all of the Partnership's cash and cash equivalents consist of a
   mutual fund that invests in U.S. treasury bills and repurchase agreements
   with original maturity dates of three months or less.

   Segment Reporting

   In June 1997, the Financial Accounting Standards Board issued SFAS No. 131,
   "Disclosures about Segments of an Enterprise and Related Information," which
   is effective for years beginning after December 15, 1997. SFAS 131
   established standards for the way that public business enterprises report
   information about operating segments in annual financial statements and
   requires that those enterprises report selected information about operating
   segments in interim financial reports. It also establishes standards for
   related disclosures about products and services, geographic areas, and major
   customers. The Partnership has one reportable segment, net leased commercial
   real estate. The Partnership evaluates performances based on net operating
   income, which is income before depreciation, amortization, interest and
   non-operating items.

2. TRANSACTIONS WITH RELATED PARTIES
   ---------------------------------

   One Winthrop Properties, Inc. ("One Winthrop" or the "Managing General
   Partner") and Linnaeus-Hampshire Realty Limited Partnership are the general
   partners of the Partnership. Winthrop Management LLC, an affiliate of One
   Winthrop, is entitled to annual property management fees equal to 1.5% of the
   excess of cash receipts over cash expenditures (excluding debt service,
   property management fees and capital expenditures) from each property managed
   by Winthrop Management LLC. For the years ended December 31, 1999 and 1998,
   Winthrop Management LLC earned $15,000 and $21,000, respectively, for
   managing the properties of the Partnership.

   Profits and losses from operations are allocated 8% to the general partners
   and 92% to the limited partners. Profits from a sale are allocated between
   the general partners and the limited partners in proportion to the cumulative
   cash distributions they have received. The general partners are allocated at
   least 1% of the profits from a sale. The general partners are entitled to 8%
   of Cash Available for Distribution (as defined in the partnership agreement),
   subordinated to a cumulative priority quarterly distribution to the limited
   partners. The general partners are also entitled to 8% of sale or refinancing
   proceeds, subordinated to certain priority distributions to the limited
   partners as provided for in the partnership agreement.

   During the liquidation stage of the Partnership, the general partners and
   their affiliates are entitled to receive distributions, subordinated to
   specified minimum returns to the limited partners as described in the
   partnership agreement.

                                      F - 9


<PAGE>



                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                          NOTES TO FINANCIAL STATEMENTS
                          -----------------------------
                     YEARS ENDED DECEMBER 31, 1999 AND 1998
                     --------------------------------------
                                   (continued)
                                   -----------

2. TRANSACTIONS WITH RELATED PARTIES (Continued)
   ---------------------------------------------

   During 1999, an affiliate of the general partner acquired, for a purchase
   price of $160 per unit, approximately 19% of the total limited partnership
   units of the Partnership (8,851.64 units).

3. REAL ESTATE LEASED TO OTHERS ACCOUNTED FOR UNDER THE OPERATING METHOD
   ---------------------------------------------------------------------

   Real estate leased to others, at cost, accounted for under the operating
   method is summarized as follows:

                                                    December 31,
                                            -------------------------

                                              1999               1998
                                          -------------     -------------
   Land                                   $  1,811,000      $  2,281,000
   Commercial buildings                      2,695,000         2,681,000
   Accumulated depreciation                   (592,000)         (506,000)
                                          -------------     ------------
                                          $  3,914,000      $  4,456,000
                                          =============     ============

   The following is a summary of the minimum anticipated future rental receipts,
   excluding percentage rents, by year, under the noncancelable portion of the
   operating leases (including leases renewed in January 2000):

                  2000......................................$    627,000
                  2001......................................     397,000
                  2002......................................     397,000
                  2003......................................     406,000
                  2004......................................     412,000
                  Thereafter................................   1,102,000
                                                            ------------
                                                            $  3,341,000
                                                            ============

   During January 1998, the Partnership leased approximately 60,000 square feet
   of the 96,000 square foot Victoria, Texas property to Hobby Lobby Creative
   Center pursuant to a lease which expires May 2008, with two renewal options
   of five years each. The previous tenant's lease (Wal-Mart) was to expire in
   December 2000, however, on January 30, 1998, the Partnership signed a lease
   termination agreement with the previous tenant whereby they would make
   certain improvements to the property, pay rent through June 1, 1998 and pay a
   termination fee in the amount of $200,000. The new lease with Hobby Lobby
   provides for a higher rental rate. The termination fee is included in other
   income.

                                     F - 10


<PAGE>



                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                          NOTES TO FINANCIAL STATEMENTS
                          -----------------------------
                     YEARS ENDED DECEMBER 31, 1999 AND 1998
                     --------------------------------------
                                   (continued)
                                   -----------

4. REAL ESTATE LEASED TO OTHERS ACCOUNTED FOR UNDER THE FINANCING METHOD
   ---------------------------------------------------------------------

   Real estate leased to others, accounted for under the financing method is
   summarized as follows:

                                                   December 31,
                                          -------------------------------
                                              1999               1998
                                          -------------     -------------

   Minimum lease payments receivable      $    340,000      $    699,000
   Unguaranteed residual value                 879,000         1,495,000
                                          ------------      ------------
                                             1,219,000         2,194,000
   Less:  Unearned income                      (80,000)         (219,000)
                                          -------------     ------------
                                          $  1,139,000      $  1,975,000
                                          ============      ============

   The following is a summary of the minimum anticipated future rental receipts,
   excluding percentage rents, by year, under the financing leases (including
   leases renewed in January 2000):

                  2000......................................$    314,000
                  2001......................................     314,000
                  2002......................................     314,000
                  2003......................................     314,000
                  2004......................................     314,000
                  Thereafter................................     340,000
                                                            ------------

                  Total.....................................$  1,910,000
                                                            ============

5. SIGNIFICANT TENANTS
   -------------------

   For the year ended December 31, 1999 approximately 95% of revenue from rental
   operations was from five tenants. For the year ended December 31, 1998 six
   tenants comprised approximately 98% of the Partnership's rental revenue.
   Approximately 32% and 18% of revenue from rental operations was from the
   Partnership's Victoria, Texas property during 1999 and 1998, respectively.
   Approximately 21% and 19% of revenue from rental operations was from the
   Partnership's Beaumont, Texas property during 1999 and 1998, respectively.
   The Partnership's Bowling Green, Kentucky property comprised approximately
   26% of revenue from rental operations in 1998. The property was sold in 1999.

6. SALE OF PROPERTIES
   ------------------

   The Partnership's Bowling Green, Kentucky property was sold to an
   unaffiliated third party on June 16, 1999 for $1,757,000 (net of closing
   costs of $143,000). The Partnership spent approximately $152,000 in
   improvements before the sale. Since the carrying value of the property was
   $1,237,000, the Partnership realized a gain of $520,000. The Partnership is
   negotiating with Wal-Mart for the settlement of insurance proceeds for
   damages sustained as a result of a hailstorm in April 1998. Insurance
   proceeds are expected to be between $500,000 and $750,000.

                                     F - 11


<PAGE>



                    WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                          NOTES TO FINANCIAL STATEMENTS
                          -----------------------------
                     YEARS ENDED DECEMBER 31, 1999 AND 1998
                     --------------------------------------
                                   (continued)
                                   -----------

6. SALE OF PROPERTIES (Continued)
   ------------------------------

   The Partnership's Ashtabula, Ohio property was sold to an unaffiliated third
   party on July 23, 1999 for $34,000 (net of closing costs of $6,000). Since
   the carrying value of the property was written down to zero, the Partnership
   realized a gain of $34,000.

   On October 27, 1999, the Partnership sold its property located in Bolivar,
   Ohio to an unaffiliated third party for $137,000 (net of closing costs of
   $11,000). Since the carrying value of the property was $39,000, the
   Partnership realized a gain of $98,000.

   On March 6, 1998, the Partnership sold its property located in Royal Oak,
   Michigan to an unaffiliated third party for $194,000 (net of closing costs of
   $6,000), resulting in a gain of $131,000.

7. TAXABLE INCOME
   --------------

   The Partnership's taxable income for 1999 and 1998 differs from net income
   for financial reporting purposes, as follows:
<TABLE>
<CAPTION>

                                                                                   1999              1998
                                                                                -------------     ------------
<S>                                                                             <C>               <C>
   Net income for financial reporting purposes                                  $   1,323,000     $ 1,277,000
         Plus:    Minimum lease payments received, net of interest
                  income earned, on leases accounted for under the
                  financing method                                                    220,000         334,000
         Minus:   Depreciation on leases accounted for under the
                  financing method and tax depreciation adjustment                    (82,000)       (121,000)
   Gain on sale of property                                                           315,000     $   (18,000)
                                                                                -------------     ------------
   Taxable income                                                               $   1,776,000     $ 1,472,000
                                                                                =============     ============

   Taxable income per Unit of Limited Partnership Interest                      $       37.28     $     29.85
                                                                                =============     ===========
</TABLE>


                                     F - 12
<PAGE>

Item 8.  Changes  in  and   Disagreements  on  Accounting  and  Financial
         ----------------------------------------------------------------
         Disclosure.
         ----------

      There were no disagreements with Imowitz Koenig & Co., LLP regarding the
1999 or 1998 audits of the Partnership's financial statements.

                                       26
<PAGE>

                                    PART III
                                    --------

Item 9.     Directors,  Executive  Officers,  Promoters and Control Persons;
            Compliance With Section 16(a) of the Exchange Act.

      The Partnership has no officers or directors. The Managing General Partner
manages and controls substantially all of the Partnership's affairs and has
general responsibility and ultimate authority in all matters affecting its
business. As of March 1, 2000, the names of the directors and executive officers
of the Managing General Partner and the position held by each of them, are as
follows:

                                                      Has Served as
                            Position Held with the     a Director or
Name                       Managing General Partner   Officer Since
----                       ------------------------   ---------------

Michael L. Ashner          Chief Executive Officer         1-96
                           and Director

Thomas C. Staples          Chief Financial Officer         1-99

Peter Braverman            Executive Vice President        1-96
                              and Director

Carolyn Tiffany            Chief Operating Officer         10-95
                              and Clerk

      Michael L. Ashner, age 47, has been the Chief Executive Officer of
Winthrop Financial Associates, A Limited Partnership ("WFA") and the Managing
General Partner since January 15, 1996. From June 1994 until January 1996, Mr.
Ashner was a Director, President and Co-chairman of National Property Investors,
Inc., a real estate investment company ("NPI"). Mr. Ashner was also a Director
and executive officer of NPI Property Management Corporation ("NPI Management")
from April 1984 until January 1996. In addition, since 1981 Mr. Ashner has been
President of Exeter Capital Corporation, a firm which has organized and
administered real estate limited partnerships.

      Thomas C. Staples,  age 44, has been the Chief Financial  Officer of WFA
since January 1, 1999.  From March 1996 through  December  1998,  Mr.  Staples
was  Vice  President/Corporate  Controller  of  WFA.  From  May  1994  through
February 1996, Mr. Staples was the Controller of the  Residential  Division of
Winthrop Management.

      Peter Braverman, age 48, has been a Vice President of WFA and the Managing
General Partner since January 1996. From June


                                       27
<PAGE>

1995 until January 1996, Mr. Braverman was a Vice President of NPI and NPI
Management. From June 1991 until March 1994, Mr. Braverman was President of the
Braverman Group, a firm specializing in management consulting for the real
estate and construction industries. From 1988 to 1991, Mr. Braverman was a Vice
President and Assistant Secretary of Fischbach Corporation, a publicly traded,
international real estate and construction firm.

      Carolyn Tiffany, age 33, has been employed with WFA since January 1993.
From 1993 to September 1995, Ms. Tiffany was a Senior Analyst and Associate in
WFA's accounting and asset management departments. Ms. Tiffany was a Vice
President in the asset management and investor relations departments of WFA from
October 1995 to December 1997, at which time she became the Chief Operating
Officer of WFA.

      One or more of the above persons are also directors or officers of a
general partner (or general partner of a general partner) of the following
limited partnerships which either have a class of securities registered pursuant
to Section 12(g) of the Securities and Exchange Act of 1934, or are subject to
the reporting requirements of Section 15(d) of such Act: Winthrop Partners 79
Limited Partnership; Winthrop Residential Associates I, A Limited Partnership;
Winthrop Residential Associates II, A Limited Partnership; Winthrop Residential
Associates III, A Limited Partnership; 1999 Broadway Associates Limited
Partnership; Nantucket Island Associates Limited Partnership; Presidential
Associates I Limited Partnership; Riverside Park Associates Limited Partnership;
Springhill Lake Investors Limited Partnership; Twelve AMH Associates Limited
Partnership; Winthrop California Investors Limited Partnership; and Winthrop
Growth Investors I Limited Partnership.

      Except as indicated above, neither the Partnership nor the Managing
General Partner has any significant employees within the meaning of Item 401(b)
of Regulation S-B. There are no family relationships among the officers and
directors of the Managing General Partner.

      Based solely upon a review of Forms 3 and 4 and amendments thereto
furnished to the Partnership under Rule 16a-3(e) during the Partnership's most
recent fiscal year and Forms 5 and amendments thereto furnished to the
Partnership with respect to its most recent fiscal year, the Partnership is not
aware of any director, officer or beneficial owner of more than ten percent of
the units of limited partnership interest in the Partnership that failed to file
on a timely basis, as disclosed in the above

                                       28
<PAGE>

Forms, reports required by section 16(a) of the Exchange Act during the most
recent fiscal year or prior fiscal years.

Item 10.  Executive Compensation.
          ----------------------

      The Partnership is not required to and did not pay any compensation to the
officers or directors of the Managing General Partner. The Managing General
Partner does not presently pay any compensation to any of its officers or
directors. (See Item 12, "Certain Relationships and Related Transactions.")

Item 11.  Security Ownership of Certain Beneficial Owners and
          ---------------------------------------------------
          Management.
          ----------

      (a)   Security Ownership of certain beneficial owners.

      No person or group is known by the Partnership to be the beneficial owner
of more than 5% of the outstanding Units at February 1, 2000, except Quadrangle
Associates I L.L.C., an affiliate of the Managing General Partner, which
acquired 8,328.48 Units (18.25%) pursuant to its tender offer commenced on
August 23, 1999. The principal office of Quadrangle Associates I L.L.C. is
located at 5 Cambridge Center, Cambridge, Massachusetts 02142.

      Under the Amended and Restated Agreement of Limited Partnership of the
Partnership dated as of June 5, 1980 (the "Partnership Agreement"), the voting
rights of the Limited Partners are limited and, in some circumstances, are
subject to the prior receipt of certain opinions of counsel or judicial
decisions.

      Under the Partnership Agreement, the right to manage the business of the
Partnership is vested in the General Partners and is generally to be exercised
only by the Managing General Partner, although the consent of the Associate
General Partner is required for all purchases, financings, refinancings and
sales or other dispositions of the Partnership's real properties and with
respect to certain other matters.

      (b)   Security ownership of management.

            None of the partners of WFA nor the general partner, officers and
directors of the General Partners owned any Units beneficially at March 1, 2000.
However, a wholly-owned subsidiary of WFA owns 210 Units and WFA owns 12 units,
which, in the aggregate, represents less than one percent of the outstanding
units. In addition, pursuant to a tender offer commenced on August 23, 1999,
Quadrangle Associates I L.L.C., an

                                       29
<PAGE>


affiliate of the Managing General Partner, acquired, for a purchase price of
$160 per unit, approximately 18.25% of the total limited partnership units of
the Partnership (8,328.48 units).

      (c)   Changes in control.

      There exists no arrangement known to the Partnership the operation of
which may at a subsequent date result in a change in control of the Partnership.

Item 12.  Certain Relationships and Related Transactions.
          ----------------------------------------------

      Under the Partnership Agreement, the General Partners and their affiliates
are entitled to receive various fees, commissions, cash distributions,
allocations of taxable income or loss and expense reimbursements from the
Partnership.

      Winthrop Management is entitled to annual property management fees, equal
to 1.5% of the excess of cash receipts over cash expenditures (excluding debt
service, property management fees and capital expenditures) from each property
it manages. For the years ended December 31, 1999 and 1998, Winthrop Management
earned approximately $15,000 and $21,000, respectively, for managing the real
properties of the Partnership.

      The General Partners are entitled to 8% of Cash Available for
Distribution, subordinated to a cumulative, priority quarterly distribution to
the Limited Partners. The General Partners are also entitled to 8% of Sale or
Refinancing Proceeds, subordinated to certain priority distributions to the
Limited Partners as provided for in the Partnership Agreement. For the year
ended December 31, 1999, the Partnership accrued a distribution from Cash
Available for Distribution to the General Partners of $242,167.

      During the liquidation stage of the Partnership, the General Partners and
their affiliates are entitled to receive distributions, subordinated to
specified minimum returns to the Limited Partners, as described in the
Partnership Agreement.

                                       30
<PAGE>

Item 13.  Exhibits and Reports on Form 8K.
          -------------------------------

      (a)   Exhibits:

            The Exhibits listed on the accompanying Index to Exhibits are filed
            as part of this Annual Report and incorporated in this Annual Report
            as set forth in said Index.

      (b)   Reports on Form 8-K - None


                                       31
<PAGE>

                                   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 by the undersigned, thereunto duly authorized.

                         WINTHROP PARTNERS 80 LIMITED PARTNERSHIP

                         By: ONE WINTHROP PROPERTIES, INC.,
                            Managing General Partner

                             By: /s/ Michael Ashner
                                -------------------------
                                      Michael Ashner
                                      Chief Executive Officer

                                     Date:  March 29, 2000

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

Signature/Name        Title                    Date
--------------        -----                    -----

/s/ Michael Ashner    Chief Executive          March 29, 2000
------------------    Officer and Director
Michael Ashner

/s/ Thomas Staples    Chief Financial Officer  March 29, 2000
------------------
Thomas Staples

                                       32
<PAGE>


                                INDEX TO EXHIBITS
                                -----------------

Exhibit                                                      Page
-------                                                      ----

 3       Amended and Restated Agreement of Limited Partnership   (1)
         of Winthrop Partners 80 dated as of June 5, 1980

  4      See Exhibit (3).

 10(a)   Property Management Agreement between Winthrop          (1)
         Partners 80 and WP Management Co., Inc. dated
         February 12, 1980

 10(b)   Documents relating to Dairymart, formerly The Lawson    (2)
         Company ("Dairymart"), property in Bolivar, Ohio

 10(c)   Documents relating to the Dairymart property in         (2)
         Creston, Ohio

 10(d)   Documents relating to the Dairymart property in         (2)
         Berkley, Michigan

 10(e)   Documents relating to the Motorola, formerly            (3)
         Duckwall-Alco Stores, Inc., property in
         Mt. Pleasant, Iowa

         Release Agreement and Assumption and Assignment of      (4)
         Lease, dated September 29, 1989

         First Amendment to Sublease, dated March 31, 1990.      (4)

         Second Amendment to Sublease, dated April 9, 1991.      (4)

 10(f)   Documents relating to the Duckwall-Alco Stores, Inc.    (3)
         property in Nebraska City, Nebraska

         Assumption and Amendment to Lease, dated September      (4)
         11, 1989

10(g)    Documents relating to the Wal-Mart Stores, Inc.         (3)
         ("Wal-Mart") property in Bowling Green, Kentucky

 10(h)   Documents relating to the Wal-Mart property in          (3)
         Victoria, Texas

10(i)    First Amendment to Lease, date October 7, 1994,         (5)
         between Winthrop Partners 80 Limited Partnership
         and Wal-Mart Stores, Inc.

16.      Letter from Arthur Andersen LLP dated September         (6)
         19, 1996.

27.      Financial Data Schedule

99.      Supplementary Information required pursuant to
         Section 9.4 of the Partnership Agreement

--------------

(1)   Incorporated  herein  by  reference  to the  Partnership's  Registration
      Statement on Form S-11, File No. 2-66725.

(2)   Incorporated herein by reference to the Partnership's Current Report on
      Form 8-K dated October 10, 1980).

(3)   Incorporated herein by reference to the Partnership's Current Report on
      Form 8-K dated January 7, 1981).

(4)   Incorporated  herein by reference to the Partnership's  annual report on
      Form 10-K dated March 31, 1992

(5)   Incorporated by reference to Registrant's Annual Report on Form 10-K for
      the year ended December 31, 1994.

(6)   Incorporated by reference to the Partnership's Current Report on Form 8-K
      dated September 23, 1996.

                                       34