The new legal twist in the long-running dispute involving the two men and advertising giant's operations in Italy is a reversal of a decision in April, when a judge said that Benatti could not move ahead legal proceedings against Sorrell.
However, according to a report in The Times this morning a hearing to decide whether there should now be a trial is slated for October 4. A WPP spokesman said earlier this year that the complaint "has absolutely no merit".
Benatti is pushing ahead on all legal fronts. In Verona, he has a civil case pending against WPP for unfair dismissal after he was fired after financial abnormalities emerged centring on a media buying company, Mediaclub, that WPP bought.
WPP called in corporate investigator Kroll to conduct a fraud investigation into the activities of its Italian media buying operations.
The legal proceedings in Milan come against the background of a High Court default judgment issued against Benatti on March 9 because he failed to appear in court.
Benatti was ordered to pay €207,000 (£142,000) in damages, equivalent to the commission he earned when he advised WPP to buy Mediaclub, in which he secretly held a stake. Last week, he was refused permission to appeal against this judgment.
Further to this, WPP is suing Benatti, again in London, for breaching his consultancy contract.
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