The Trustee Savings Bank (or TSB as it was commonly known) was a British financial institution

Financial institution

In financial economics, a financial institution is an institution that provides financial services for its clients or members. Probably the most important financial service provided by financial institutions is acting as financial intermediaries...

 which specialised in accepting savings deposits from the poor. They did not trade their shares on the stock market

Stock market

A stock market or equity market is a public entity for the trading of company stock and derivatives at an agreed price; these are securities listed on a stock exchange as well as those only traded privately.The size of the world stock market was estimated at about $36.6 trillion...

 and, unlike mutual

Mutual organization

A mutual, mutual organization, or mutual society is an organization based on the principle of mutuality. Unlike a true cooperative, members usually do not contribute to the capital of the company by direct investment, but derive their right to profits and votes through their customer relationship...

ly held building societies, depositors had no voting rights nor the ability to direct the financial and managerial goals of the organisation. Directors were appointed as trustee

Trustee

Trustee is a legal term which, in its broadest sense, can refer to any person who holds property, authority, or a position of trust or responsibility for the benefit of another...

s (hence the name) on a voluntary basis.