According to reports, the judgment was handed down on March 9, but not revealed until the weekend, when the Sunday Telegraph reported on the win.
The paper said that the judgment was made by default, because neither Benatti nor his representatives appeared in court.
The sum represents the commission made by Benatti when he advised WPP on the acquisition of the Italian media agency Mediaclub, which WPP bought three years ago for £14m.
WPP later discovered that Benatti owned a stake in Mediaclub, and Sir Martin Sorrell, WPP chief executive, sacked him in January.
Benatti has objected to his treatment, saying that he only indirectly owned a small stake in Mediaclub through a Scottish investment fund in which he had invested since 1999.
Despite this first victory for Sorrell, the case will drag on because damages for the claim remain to be settled.
The Sunday Telegraph reports that WPP plans to submit further evidence showing that Benatti in fact owned a majority stake in Mediaclub. Benatti has filed his own suit against WPP.
In another boon for lawyers, Daniela Weber, the WPP Italy chief operating officer, is suing The Sunday Times over allegations she had a relationship with Benatti.
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