The New York-based firm voted Compagnoni into the partnership last week after a recruitment process that began only a month ago.
Along with Compagnoni, Weil also elected Lovells senior assistant and rising star Jonathan Wood to the partnership.
Wood is understood to have been on the partnership track at the UK firm. Consultant Alison Hampton is also leaving Lovells for Weil.
The two-partner haul will take Weil’s private equity capability in London to five partners, the others being Mike Francies, Mark Soundy and Will Rosen.
A Weil source said: “Our stated ambition is to become the world leader in private equity and the number one private equity firm in London and Europe.”
The move caps a series of private equity hires by Weil across Europe in the past two years, most notably David Aknin from Linklaters‘ Paris office in 2003.
Two years ago, the US firm nearly hired Clifford Chance private equity stars Matthew Layton and James Baird, but they were persuaded to stay at the magic circle firm.
In the US, Weil acts for Hicks Muse Tate & Furst and Providence, among others. The UK end has acted for Apax, Lion Capital, Bridgepoint and Candover among others.
At Lovells, Compagnoni regularly acted for Advent International, the Barclay brothers, Terra Firma, HG Capital and 3i. His book of business has been touted by several sources to be some £5m per year.
The London market has been awash with rumours about private equity partner moves. Compagnoni was widely expected to leave Lovells for a US firm, particularly since the resignation of his colleague Oliver Felsenstein in Germany for Clifford Chance last year.
Despite considerable efforts on the part of Lovells’ management in the past month to persuade him to stay, Compagnoni formally handed in his resignation on Thursday morning (5 February). His notice period has not yet been announced.
Compagnoni’s move underlines the growing market share of US-headquartered firms in the private equity sphere. Last year, Simpson Thacher & Bartlett hired Allen & Overy banking partner Tony Keal as part of its efforts to shore up its European representation of key client KKR. Kirkland & Ellis is also known to be targeting the market.
Compagnoni’s departure leaves Lovells with only a representative capability in private equity. It is understood that corporate partner Leah Dunlop will, as a temporary measure, head the team.
In a statement, Lovells managing partner David Harris said: “We are, of course, immensely disappointed to lose Marco, with whom we remain on very good terms. We are committed to rebuilding the UK end of our private equity practice.”
Compagnoni told The Lawyer: “I’ll be sad to leave friends and colleagues at Lovells. I’ve worked with them for 18 years. But the opportunity of going to a firm such as Weil Gotshal, with its US platform and excellent reputation, is too good an opportunity to miss.”
Weil’s London management has now vowed to build up its acquisition finance capability to support the private equity business.
A Weil Gotshal source told The Lawyer: “Everyone knows we’re looking for acquisition finance lawyers. It’s now a priority and we need to get that right.”
The source added: “But in private equity, we’re full, by the way.”