Multi-Family OfficeRIA · CRD 128590SEC-RegisteredPrivate Fund Adviser

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Abacus Wealth Partners

Abacus Wealth Partners was founded in 2004 by Brent Kessel and Spencer Sherman after they built a fee-based financial planning practice. The firm now manages...

Abacus Wealth Partners logo

Abacus Wealth Partners

Abacus Wealth Partners was founded in 2004 by Brent Kessel and Spencer Sherman after they built a fee-based financial planning practice. The firm now manages multigenerational assets for affluent households. The firm allocates across public markets and private impact investments with emphasis on ClimateTech. It structures client portfolios through direct holdings and mission-related vehicles. Geographic focus remains North America. The firm holds Certified B Corporation status since 2007 and maintains membership in 1% for the Planet. Abacus maintains four offices and employs named principals including Co-CEOs Neela Hummel and Mary Beth Storjohann. No dated operational events from the last 24 months appear in available records.

General information

Firm type

Multi Family Office

Year founded

2004

Location

Region

North America

Country

United States

City

Santa Monica

Corporate office

429 Santa Monica Blvd, Suite 500, Santa Monica, CA 90401

Additional offices

Sebastopol, CA · San Carlos, CA · Ardmore, PA

Principals

Brent Kessel

Founder and Financial Advisor

Spencer Sherman

Founder and Financial Advisor

Neela Hummel

Co-CEO and Financial Advisor

Kate Barron-Alicante

Director of Impact and Financial Advisor

Altss tracks 1 additional named team member for this firm — including direct investment leads, IR, and operating principals not listed on the public website.

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Sector focus

ClimateTech

Frequently asked questions

Who runs investment decisions at Abacus Wealth Partners?

Brent Kessel and Spencer Sherman founded the firm. Neela Hummel and Mary Beth Storjohann serve as Co-CEOs. Kate Barron-Alicante directs impact initiatives.

How does Abacus Wealth Partners source proprietary deal flow?

The firm draws from its network of fee-only advisors and impact-focused relationships. It participates in mission-related investing opportunities aligned with client values.

Is Abacus Wealth Partners structured as a single family office or does it operate more like a venture firm?

Abacus operates as a multi-family office. It provides investment management, philanthropy guidance, and family governance to multiple affluent households.

Does Abacus Wealth Partners participate in fund commitments or only direct deals?

The firm uses both fund commitments and direct holdings within impact-aligned portfolios. Specific allocation splits are not publicly detailed.

Where does the underlying wealth come from?

Wealth origin is not publicly attributed to a specific family branch or operating company.

Profile maintained by using OSINT (open-source intelligence), regulatory filings, licensed data partners, and verified direct submissions. Read the methodology. Last updated: . Continuous refresh with full update cycles at least every 30 days.

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