Dinosaur chief executive, Grant Mercer, has left the Manchester agency along with business development director Samantha Legget.
The Drum broke the news of Mercer's appointment in September 2007, when the former Tequila\\Manchester chief exec and ex-managing director of MKP was unveiled as the agency's new CEO.
It soon emerged, however, that Mercer was acting only on a part-time basis, working with the agency for just two days a month in an advisory role.
The circumstances surrounding Mercer's departure are unclear, with the agency's head, Mark Beaumont, currently on holiday.
Legget, meanwhile, is reputed to have had her contract terminated after a year at the Northern Quarter-based agency.
Despite the departures, Dinosaur remains in the middle of a recruitment drive, aiming to fill a number of positions including managing director.
Linsey Hales has joined the team in a senior creative role, after 12 years with Leeds-based Elmwood.
Hales, who has worked on brands including Durex, Asda and Halifax, will work alongside art director Dan Pitchford and report to Beaumont.