Williams and Campbell's stake will be reduced to a little under 49 per cent with the introduction of an employee equity scheme for the 25-strong New York and London firm. Publicis will consolidate Capital's accounts within the group.
As yet there have been no further changes to Capital's board and management following the departure last May of Nick Lockwood, who set up Capital in 2003 with Campbell and Williams.
Publicis's move on Capital comes just seven months after the group poached Smithfield director Nick Bastin. He joined Publicis Consultants' London office, ostensibly to build the firm's financial comms practice from an office working mainly for UK-listed European clients.
Market sources suggested last week that Publicis could try to buy Financial Dynamics from venture capital firm Advent International.
However, FD CEO Charles Watson said neither the agency nor Advent had had talks with any third party about selling the firm.