Simmons & Simmons’ Italian rainmaker Bruno Gattai has resigned from the firm and is expected to launch a practice for US firm Dewey Ballantine.

Simmons’ senior partner Janet Gaymer said that Gattai had told partners some time ago that he was reconsidering his future with the firm, before finally resigning this week. “This has not come as a surprise,” she said.

A number of assistants and clients are likely to move with Gattai.

It is understood that he has not yet confirmed to Simmons where he is going. However, he could take his pick of the US firms eager to break into Italy and sources say that Dewey Ballantine is Gattai’s most likely choice.

Simmons’ Italian practice has been a gem in the crown of its international practice since it merged with Eugenio Grippo’s firm in 1993. Gattai joined with Grippo, who has since left for Gianni Origoni (now Gianni Origoni Grippo & Partners). “Bruno has made an enormous contribution to the growth of the practice, but it is time for both of us to move on,” said Gaymer.

Simmons’ Italian turnover has increased year on year and profits per partner for 2002/2003 are understood to have been above Simmons’ firmwide average of £300,000. But the office has also fallen victim to the high level of partner turnover suffered by many international firms in Italy. Most recent to go was Simmon’s head of commercial Enrico Zattoni, who took a local partner, senior consultant and 10 associates to corporate finance boutique Morano & Associati.

Simmons retains 12 partners in Italy, including big biller Marco Franzini. Head of financial services Richard Slater is giving up his role to move to Italy as managing partner with effect from 1 September this year. His move is understood to be unrelated to Gatti’s resignation as the two have been good friends since Slater helped negotiate the original merger.