Hall joined Starcom in October as its first strategic planning director, with a brief to champion consumer-focused research at the agency and as executive director, with responsibility for the research and intelligence unit.
It is not clear whether he will be replaced or whether his role has been made redundant as Starcom Motive refused to comment.
Hall worked across the entire client portfolio of Starcom Motive and MediaVest, on on new-business briefs and to develop deeper relationships with the creative agencies.
Before joining Starcom, Hall ran his own consumer research consultancy called Informer, which worked with clients including Allied Domecq, Nike and Coca-Cola, until the consultancy closed last year.
Hall has also worked in research at Taylor Nelson and on the client side at Bayer. It is not clear what he will do next.
When Hall was appointed he said: "Having looked so long at brands from an independent consumer viewpoint it's clear to me that media is where it's at."
Starcom Motive was recently moved into the French advertising network, after Publicis bought out Bartle Bogle Hegarty's 51% stake to sit alongside its existing shop MediaVest, which was recently renamed in the UK as Starcom MediaVest in line with the rest of the world.
The management lineup of the two companies in the UK has stayed the same. At the helm of Starcom Motive remains chief executive Mark Cranmer, while Jim Marshall heads up Starcom MediaVest. The two companies will continue to operate separately.
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