Taylor Wessing, the City law firm, has sued an American rival for $5 million (£2.6 million) for allegedly illegally poaching several partners from its Paris office.

Taylor Wessing, the City law firm, has sued an American rival for $5 million (£2.6 million) for allegedly illegally poaching several partners from its Paris office.

Earlier this week, Taylor Wessing asked a court in New York for an injunction preventing 12 of the 15 non-equity partners in its Paris office from joining Nixon Peabody, a Manhattan-based law firm. It claims that the “unlawful raid” would cause “immediate and irreparable harm” to its French business.

The dispute centres around merger talks held between Taylor Wessing’s French arm and Nixon Peabody which began in July 2007.

A source close to Taylor Wessing told Times Online that the talks began without the knowledge of partners in the UK and Germany and were called off in November 2007 after those partners became aware of what was going on.

Yet although the talks were ended, the managing partner of the firm’s Paris office, Arnaud de Senilhes, “surreptitiously continued negotiations with Nixon”, according to court documents.

Mr de Senilhes has since resigned from Taylor Wessing. He is not listed in Nixon Peabody’s staff directory.

Taylor Wessing’s claim is based on a non-disclosure agreement signed between its French arm and Nixon Peabody when the merger talks began.

Taylor Wessing alleges that Nixon Peabody violated an undertaking that it would not attempt to woo its lawyers in the event that discussions collapsed.

However, Nixon Peabody claims that a letter sent by Taylor Wessing calling off the merger nullified any such undertaking.