Single Family Office

Updated:

Thamesis

Sir Martyn Arbib founded Thamesis after building Perpetual. Family members Annabel Nicoll, Benjamin Arbib and James Arbib serve as directors.

Thamesis logo

Thamesis

Sir Martyn Arbib founded Thamesis after building Perpetual. Family members Annabel Nicoll, Benjamin Arbib and James Arbib serve as directors. The office maintains a multi-generational mandate centered on capital preservation. Thamesis deploys across private equity, real estate, hedge funds, private credit, infrastructure and natural resources. It executes through direct co-investments and SPVs alongside fund commitments. Confirmed geographic reach covers Europe and North America. Sector exposure includes AgriTech & FoodTech, Energy Transition & Renewables, Industrial Tech, Mobility & Transportation, WaterTech and FinTech. The firm lists 61 Grosvenor Street and a London residential portfolio among its real assets. It also holds interests in thoroughbred racing and the River & Rowing Museum. Cressida Myers was appointed CEO in 2026. Thamesis operates with an advisory board that includes Lord Massey of Hampstead. Governance separates investment decisions from the philanthropic vehicles The Annabel Arbib Foundation, The A Team Foundation and The Tellus Mater Foundation.

General information

Firm type

Single Family Office

Location

Region

Europe

Country

United Kingdom

City

London

Corporate office

London, United Kingdom

Principals

Sir Martyn Arbib

Founder

Annabel Nicoll

Director

Benjamin Arbib

Director

James Arbib

Director

Cressida Myers

CEO

Lord Massey of Hampstead

Advisory Board Member

Sector focus

AgriTech & FoodTechCircular EconomyEnergy Transition & RenewablesIndustrial TechMobility & TransportationSupply Chain & LogisticsWaterTechFinTech

Frequently asked questions

Who runs investment decisions at Thamesis?

Cressida Myers serves as CEO. Sir Martyn Arbib founded the office. Family directors Annabel Nicoll, Benjamin Arbib and James Arbib participate in oversight.

Where does the underlying wealth come from?

Sir Martyn Arbib founded Perpetual, the source of the family wealth now stewarded by Thamesis.

Does Thamesis participate in fund commitments or only direct deals?

Thamesis uses both fund commitments and direct co-investments through SPVs.

Which sectors does Thamesis target?

Confirmed focuses include AgriTech & FoodTech, Energy Transition & Renewables, Industrial Tech, Mobility & Transportation, WaterTech and FinTech.

How is Thamesis related to philanthropic structures?

The office maintains separate vehicles including The Annabel Arbib Foundation, The A Team Foundation and The Tellus Mater Foundation.

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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