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Nonprofit · EIN 94-6104011

BELVEDERE-TIBURON LANDMARKS SOCIETY

Tax-exempt · TIBURON, CA 94920

Financials

$709K$475K2023$536K$487K2024$367K$536K2025
Revenue Expenses · by fiscal year end
Financials of BELVEDERE-TIBURON LANDMARKS SOCIETY by year, from its e-filed returns
Year endedFormRevenueExpensesNet incomeTotal assetsLiabilitiesNet assets
December 31, 2025990$367,386$536,112-$168,726$5,073,234$63,786$5,009,448
December 31, 2024990$535,586$486,609$48,977$4,903,404$55,566$4,847,838
December 31, 2023990$709,062$474,820$234,242$4,627,371$42,406$4,584,965
Financial details: 990 for the year ended December 31, 2025

Revenue

Contributions, gifts and grants
$211,656
Program service revenue
$111,970
Investment income
$0
Net income from fundraising events
$27,796
Net income from sales of inventory
-$2,960
Other revenue
$43,760

Expenses

Grants and similar amounts paid
$0
Other salaries and wages
$115,502
Salaries, compensation and benefits (total)
$154,821
Professional fundraising fees
$0
Accounting fees
$11,873
Occupancy
$58,958
Program services (functional)
$220,957
Management and general (functional)
$315,155

Balance sheet and other

Total assets, start of year
$4,903,404
Total assets, end of year
$5,073,234
Total liabilities, end of year
$63,786
Net assets, end of year
$5,009,448
Land, buildings and equipment
$2,360,721
Publicly traded securities
$2,384,295
Gross unrelated business income
$2,011
Gross receipts
$370,346
Employees
0
Volunteers
0
Year formed
1957
State of legal domicile
CA

From the e-filed returns the IRS publishes as XML (latest three processing years; amended returns replace the original). PDF copies at the IRS.

Officers, directors and key employees

As listed on the 990 for the year ended December 31, 2025, highest compensation first.

NameTitleHours / weekCompensation
PHIL CASSOUVICE - PRESIDENT
Trustee or director, Officer
1$0
HELEN LINDQVISTSECRETARY
Trustee or director, Officer
1$0
JIM ALLENCO-TREASURER
Trustee or director, Officer
1$0
BROOKE HALSEYCO-TREASURER
Trustee or director, Officer
1$0
PETER BROOKSBOARD MEMBER
Trustee or director
1$0
EVA BUXTONBOARD MEMBER
Trustee or director
1$0
BOB HARRISONBOARD MEMBER
Trustee or director
1$0
SUZANNE WHITEBOARD MEMBER
Trustee or director
1$0
MARK FREIBERGPRESIDENT
Trustee or director
1$0
PATRICIA A FLAXEXECUTIVE DIRECTOR
Officer
40$0
990 for the year ended December 31, 2024: 10 people
NameTitleHours / weekCompensation
PATRICIA A FLAXEXECUTIVE DIRECTOR
Officer
40$91,415
PHIL CASSOUPRESIDENT
Trustee or director, Officer
1$0
HELEN LINDQVISTSECRETARY
Trustee or director, Officer
1$0
JIM ALLENCO-TREASURER
Trustee or director, Officer
1$0
BROOKE HALSEYCO-TREASURER
Trustee or director, Officer
1$0
PETER BROOKSBOARD MEMBER
Trustee or director
1$0
EVA BUXTONBOARD MEMBER
Trustee or director
1$0
BOB HARRISONBOARD MEMBER
Trustee or director
1$0
SUZANNE WHITEBOARD MEMBER
Trustee or director
1$0
MARK FREIBERGBOARD MEMBER
Trustee or director
1$0
990 for the year ended December 31, 2023: 10 people
NameTitleHours / weekCompensation
PHIL CASSOUPRESIDENT
Trustee or director, Officer
1$0
HELEN LINDQVISTSECRETARY
Trustee or director, Officer
1$0
JIM ALLENCO-TREASURER
Trustee or director, Officer
1$0
BROOKE HALSEYCO-TREASURER
Trustee or director, Officer
1$0
PETER BROOKSBOARD MEMBER
Trustee or director
1$0
EVA BUXTONBOARD MEMBER
Trustee or director
1$0
BOB HARRISONBOARD MEMBER
Trustee or director
1$0
GABRIELLE KEILBOARD MEMBER
Trustee or director
1$0
SUZANNE WHITEBOARD MEMBER
Trustee or director
1$0
PATRICIA A FLAXEXECUTIVE DIRECTOR
Officer
40$0

Address and contacts

Address (IRS master file)
1550 TIBURON BLVD STE M, TIBURON, CA 94920-2529
Principal officer (990 for 2025)
PATTY FLAX, PO BOX 134, TIBURON, CA 94920
Signed the 990
PATTY FLAX, EXECUTIVE DIRECTOR
Phone
(415) 435-1853
Return prepared by
WINSTON AND CO ACCOUNTANCY CORPORATION

California records

California keeps its own records of charities and corporations. Search them by EIN 94-6104011 or by the name BELVEDERE-TIBURON LANDMARKS SOCIETY.

Attorney General, Registry of Charities and Fundraisers
Registration status and filed reports (CT-TR-1, RRF-1)

Mission

PRESERVATION AND CONSERVATION OF LOCAL HISTORICAL BUILDINGS AND MAKING THE BUILDINGS AVAILABLE FOR PUBLIC ACCESS

990 for the year ended December 31, 2025

Program accomplishments

  • PRESERVATION OF LOCAL LANDMARKS
    Expenses $220,957 · revenue $111,970

What it must file and when

IRS records say it files Form 990 or 990-EZ. Based on its last return; a smaller organization may file the 990-N. Its accounting year ends in December, so each return is due on the 15th day of the 5th month after that.

Tax yearYear endedDueIRS public records
2025December 31, 2025May 15, 2026990 on file
2024December 31, 2024May 15, 2025990 on file
2023December 31, 2023May 15, 2024990 on file

IRS record

EIN
94-6104011
Tax-exempt status
501(c)(3): Charitable, religious, educational or scientific organization
Foundation status
Publicly supported organization (170(b)(1)(A)(vi))
Donations deductible (Pub 78)
Public charity, 50% deduction limit
Exempt since
1962
Accounting year ends
December
Files
Form 990 or 990-EZ
Assets (IRS master file)
$5,073,234
Income (IRS master file)
$370,346

Filing history

FormYear endedRevenueExpensesAssetsReturn
990December 2025$367,386$536,112$5,073,234XML
990December 2024$535,586$486,609$4,903,404XML
990December 2023$709,062$474,820$4,627,371XML
990December 2022$416,267$438,399$4,143,572IRS
990December 2021–––IRS
990December 2020–––IRS
990December 2019–––IRS
990December 2018–––IRS

990-N: the IRS bulk file holds only the latest e-Postcard per organization; earlier years come from archived copies of that file since 2020 and can have gaps (the IRS e-Postcard search lists every one). 990, 990-EZ, 990-PF, 990-T: every e-filed return in the IRS e-file index since 2019; XML for the latest three processing years, amounts from the IRS Statistics of Income extracts before that. PDF copies and determination letters at the IRS (search EIN 94-6104011).

Questions about BELVEDERE-TIBURON LANDMARKS SOCIETY

What is the EIN of BELVEDERE-TIBURON LANDMARKS SOCIETY?
The employer identification number (EIN) of BELVEDERE-TIBURON LANDMARKS SOCIETY is 94-6104011.
Is BELVEDERE-TIBURON LANDMARKS SOCIETY tax-exempt?
Yes. The IRS lists it as tax-exempt under section 501(c)(3) since 1962.
Are donations to BELVEDERE-TIBURON LANDMARKS SOCIETY tax-deductible?
Yes. It is listed in IRS Publication 78 (Public charity, 50% deduction limit).
Which annual return does BELVEDERE-TIBURON LANDMARKS SOCIETY file?
Form 990 or 990-EZ. Based on its last return; a smaller organization may file the 990-N.
When is the next return of BELVEDERE-TIBURON LANDMARKS SOCIETY due?
The return for tax year 2026 (the year ending December 31, 2026) is due May 17, 2027. Form 8868 extends it by six months; the 990-N cannot be extended.
When did BELVEDERE-TIBURON LANDMARKS SOCIETY last file with the IRS?
The latest return in the IRS public files is the 990 for the year ended December 2025.
Who is the principal officer of BELVEDERE-TIBURON LANDMARKS SOCIETY?
The 990 for the year ended December 31, 2025 names PATTY FLAX.
Who are the officers and directors of BELVEDERE-TIBURON LANDMARKS SOCIETY?
The 990 for the year ended December 31, 2025 lists 10 people; 0 received compensation from the organization.
How much revenue does BELVEDERE-TIBURON LANDMARKS SOCIETY have?
On its 990 for the year ended December 31, 2025 it reported revenue of $367,386, expenses of $536,112 and total assets of $5,073,234 at year end.

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