Italian leader Gianni Origoni Grippo & Partners is to split, with the executive committee and around 100 lawyers breaking away to form their own practice.

The firm, which has around 350 lawyers in total, is preparing an announcement on the news, which will represent one of the most significant splits of a leading European independent.

The departing group consists of around 16 partners and is led by a number of the firm's top names, with executive committee members Alberto Giampieri, Filippo Troisi and Bruno Bartocci all leaving. The recently-appointed managing partner, M&A specialist Giovanni Nardulli, is also leaving.

The group of partners plus around 90 additional lawyers represent nearly a third of the firm and will set up their own firm, which will be based in Milan, Rome and London. Nardulli will head the new firm, which is yet to be named.

It is understood the departing group consists of the firm's entire banking practice and all of heads of department.

The move is understood to follow disagreements between the firm's executive committee and founder Francesco Gianni.

One Gianni insider told Legal Week the rift began after the firm re-jigged its management structure in June this year. The move saw Gianni step up from managing partner to senior partner and the formation of a new executive committee, headed by Nardulli.

It is thought that Gianni, fellow name partner GianBattista Origoni and a group of other partners confronted Nardulli late last week over issues including the firm's hiring policy and this is when the group announced its plans to leave.

The source told Legal Week: "The firm is reviewing the situation to see what will happen but the most important factor is that a majority of partners including Gianni are going to stay."

Gianni for many years had a formal alliance with magic circle giant Linklaters but in 2004 the firms severed ties with one another following Gianni's reluctance to merge.

A former Gianni partner said: "It will leave Gianni with more than half the business but it is a move that many in the market have expected for a while. It is the biggest break up in Italy for a long time."

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