Founded in 1976, in implementation of a specific legal provision within the sphere of the IRI initiatives and therefore as a prevalently publicly owned company, Sogei undertook to create the Tax Register, to automate the management of checking tax returns and to monitor tax payments, meeting the Italian Finance Administration's need to implement the complex tax reforms of 1974, which increased the number of taxpayers from 4 million to 25 million.
 
After being taken over by Telecom Italia in 1997, up to which point it had been entirely privately held, it returned to public ownership in July 2002 when the entire share capital was bought by the Ministry of Economy and Finance. The new public status will ensure operational continuity and that a central computerised tax service is developed for the country whilst Sogei's technical and fiscal knowledge and expertise is maintained and grown as the Revenue Authority's technological partner.

As a 100% publicly owned joint stock company, in application of the provisions in force relative to public service contracts issued in implementation of the Community directives on the subject (legislative decree no. 163 of 12th April 2006 and successive amendments and additions), Sogei has taken on the nature of a "public rights company" and the qualification of "contract awarding administration".