Allen & Overy (A&O) global private equity co-head Derek Baird has resigned to join Simpson Thacher & Bartlett in London.

Baird will join the elite US firm as a partner in the City corporate group, taking the total number of partners in the London office to 14. He will make the move in the new year.

Baird joined A&O from legacy Lovells in 2006 as part of a concerted effort from the magic circle firm to build up its footprint in private equity. His client portfolio has in recent years included key private equity names such as Advent International, Charterhouse Capital Partners and 3i. He had been a partner at Lovells since 2002 after joining from Scotland's Dickson Minto.

The news marks the latest move by a magic circle partner to a US firm in London after a spate of such hires over the last 12 months, including A&O arbitration partners Stephen Jagusch and Anthony Sinclair, who left to join Quinn Emanuel Urquhart & Sullivan.

Meanwhile, Freshfields Bruckhaus Deringer duo Simon Witty and Jonathan Cooklin moved to Davis Polk & Wardwell in London in the first half of the year.

Simpson Thacher has a longstanding reputation for its strength in the private equity sector, with other big-name partners in the firm's London office including former Clifford Chance partners Adam Signy and Jason Glover. The firm recently advised Melrose on its £1.5bn acquisition of German utility meter manufacturer Elster Group this summer, as well as KKR's £800m acquisition of UK oil and gas company Acteon.

Simpson chairman Pete Ruegger said: "Derek's experience and recognised expertise fit well with our highly regarded mergers and acquisitions and acquisition finance practices.

"His addition will enhance our ability to offer outstanding legal services to our clients in the UK, continental Europe and throughout the world."

In a statement, A&O said: "Derek Baird has decided to leave A&O. We would like to thank him for the contribution he has made during his time at here and wish him all the best for the future."

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