The agency is not seeking a replacement in Le Grice's role of chief innovation officer.
Blue Rubicon CEO Gordon Tempest-Hay said: "Craig joined Blue Rubicon to complete a particular job; the build and launch of our knowledge resource. Having delivered that, it’s a natural time for him to move on and we wish him all the best in his new role. It will be the responsiblity of our account teams to embed his work."
The knowledge system Le Grice worked on formed part of a £5m investment drive, including a new accounting system and the acquisitions of Open Road and Hesleden Partners, in the period between Blue Rubicon's late 2012 deal with private equity backer LDC and the first quarter of this year.
