[Minutes of 80 meetings of the Nebula Implementation Study Group, established originally to consider provision by Ferranti Ltd. of computing system for Prudential Assurance Co. Ltd, 1963-1971. 1 lever-arch file. The N.I.S.G. originally comprised representatives of the Prudential and Ferranti companies. With meeting 8 (26 Nov 1963) Ferranti had become I.C.T. Ltd; with meeting 62 (11 Jul 1968) I.C.T. Ltd had become I.C.L. Ltd; Meetings were regular until no.79 (1 Jul 1970); special meeting 79a was convened on 7 Jan 1971. An 'operating system' was to be provided for Prudential, ensuring that 'adequate programming development facilities are present within the structure of Nebula' and that 'maximum efficiency from the Nebula language is achieved']