Despite individual specialities, all the member firms will form a central pool that Vivendi companies will use.
Firms were invited to tender for the places last autumn. They were asked to prepare written submissions on a range of criteria and on a range of practice areas. There were no face-to-face interviews or beauty parades.
There were 15 specific questions the firms had to address as part of the tender. These included questions on personnel, fee rates, likely lawyer teams and confidentiality.
For some firms, such as Theodore Goddard and Boyes Turner, the appointments mark the first time that they have been formally appointed to the panel, although both firms have worked for the group before.
Theodore Goddard, for example, has long-term relationships with group companies Universal and Onyx.
Douglas Evans, head of planning and environment at Theodore Goddard, led the bid. He says that at this stage he cannot put a value on the panel place, but adds that the group is an "excellent client".
Reading-based Boyes Turner tendered on corporate as well as commercial property and employment.
Client partner Roy Butler, who sits in the corporate practice, led the bid. He says: "We are only a 17-partner firm so yes, we are very pleased with the win."
Vivendi is the world's second largest media company. It started life as a French state contractor with more than 2,000 subsidiaries.
But since the mid-1990s, most of the utility companies have been sold and it has concentrated on establishing itself as a leading player in entertainment.
Vivendi UK general counsel Michael Butcher led the review.