Lovells is advising BNP Paribas on its defence of allegations over sex discrimination despite losing key employment partner Lisa Mayhew to Jones Day last year.
Mayhew was the lead partner who won the high-profile sex discrimination battle for Merrill Lynch against former employee Stephanie Villalba in a potential claim of £7.8m.
She was also a key employment adviser to BNP Paribas, which has also turned to Clyde & Co in the past.
While Merrill Lynch has moved with Mayhew to Jones Day, Lovells has managed to hang on to its institutional relationship with BNP Paribas.
Partner Elizabeth Slattery will head the employment team at Lovells this time around, assisted by associate Vanessa Hogan and instructing Thomas Linden QC of Matrix chambers.
Linden was junior counsel on the Merrill Lynch case before he took silk. Nicholas Underhill QC of Fountain Court Chambers led on that case until his appointment to the bench in January 2006, when Linden took charge.
The appellant in this case, Katharina Tofeji, alleges that, following the birth of her daughter, BNP Paribas made it difficult for her to return to work on a part-time basis and referred to "a bet going round" that she would not return to work.
In a statement, BNP Paribas said: "BNP Paribas denies Ms Tofeji's allegations of discrimination and will continue to defend strenuously the complaints against it and against its current and former employees."
Russell Jones & Walker solicitor Samantha Mangwana is advising Tofeji.