Board of Trade and successors: Companies Division: Registered Files (COS Annual Series)...

In 1941, the Companies Division of the Board of Trade was renamed the Insurance and Companies Department. By 1964 the Department's name had been expanded to Insurance and Companies Department and Bankruptcy Department to reflect its responsibilities in relation to company liquidations.

The Companies Division's major tasks were general responsibilites under the Companies and Bankruptcy Acts and the Insurance Companies Act 1958. It was also concerned with changes in Company Law, investigations into firm's activities and affairs, including winding-up under the Companies Act 1948, and international negotiations on insurance and company law. In addition, the Division was responsible for the Industrial and Provident Societies Bill 1963 and the Protection of Depositors Act 1963, the Prevention of Fraud (Investments) Act 1958, including Unit Trusts, the Registration of Business Names Act 1916, and was concerned with consultations on the Company Law (Jenkins) Committee Report leading to the Companies Act 1967.

On 1 March 1973, the Department of Trade and Industry reorganised insurance, companies and bankruptcy work into three separate divisions, each headed by an Under Secretary. These were named the Insurance Division, the Companies Division and the Insolvency Service (InsS).

The Insolvency Service was concerned with all aspects of insolvency policy, including questions relating to the European Economic Community (EEC), HQ administration of the Official Receiver Service, the provincial Official Receiver Service, statutory responsibilities in relation to Trustees and Liquidators and the accounting and management of funds. Branch 1 dealt with bankruptcy matters and Branch 2 consisted of the Official Receiver Service in the High Court.

In April 2006 Companies Investigation Branch merged with the Insolvency Service.