A month after Wachtell, Lipton, Rosen & Katz executive compensation partner Jeremy Goldstein left the venerable Am Law 100 firm to start his own practice, the country’s most profitable shop on a profits-per-partner basis has looked outside its ranks to find a replacement in Simpson Thacher & Bartlett partner Andrea Wahlquist.

Wahlquist, 44, joined Simpson Thacher in 1997 and became a leading member of the firm’s executive compensation and employee benefits practice in New York. She was part of a team of Simpson Thacher lawyers honored by The American Lawyer as Dealmakers of the Year in 2007 for their work on behalf of longtime private equity client KKR. She left the 835-lawyer firm on May 23 of this year to take her transactional expertise to Wachtell, which saw Goldstein leave in early June.

News of Wahlquist’s potential move to 260-lawyer Wachtell was first noted in a June 4 moves column by The Deal, an M&A trade publication and former affiliate of The Am Law Daily, which attributed her departure to an unidentified source familiar with the matter. Wahlquist’s biography page appeared on Wachtell’s website a week ago.

Wahlquist did not respond to multiple requests for comment about her move to Wachtell, nor did Daniel Neff and Edward Herlihy, cochairmen of the firm’s executive committee. (Herlihy was traveling Monday.) A Wachtell spokeswoman did not respond to a request for comment on the matter, although a source familiar with Wahlquist’s move says Goldstein recommended her to the firm.

From what The Am Law Daily can determine, Wachtell’s hire of Wahlquist is only the firm’s fourth partner-level lateral hire in its storied history. Back in 2007, The American Lawyer reported on Wachtell’s third major hire in Michael Segal, a former cohead of the executive compensation and employee benefits practice at Paul, Weiss, Rifkind, Wharton & Garrison in New York, to fill a void left by the departure of former Wachtell executive compensation partners Adam Chinn and Michael Katzke.

Other laterals brought on by Wachtell over the years include current tax department head and of counsel Peter Canellos, who joined the firm back in 1977 from Cravath, Swaine & Moore, and antitrust partner Ilene Knable Gotts, who came aboard from Foley & Lardner two decades later.

Goldstein cited Chinn—architect of the “Chinn Up,” a lucrative compensation package for corporate executives—as a mentor and attributed his own decision to leave Wachtell in June to changes in the executive compensation space, some spurred on by the so-called activist investors that have targeted many of the firm’s corporate clients.

Wachtell once again topped the Am Law 100 rankings last year with profits per partner of nearly $4.8 million, while Simpson Thacher came in eighth place as average partner earnings hit almost $3.2 million, according to the most recent data compiled by The American Lawyer.

While lateral partner hires are extremely rare at Wachtell, partner-level departures are also equally infrequent at Simpson Thacher. Last year, the firm saw young M&A partner Sean Rodgers decamp to Kirkland & Ellis, while antitrust partner Aimee Goldstein and financial institutions partner Stacie McGinn both retired. McGinn joined Simpson Thacher in early 2011 from Bank of America, where she was deputy general counsel, and Goldstein came aboard a decade earlier from Clifford Chance after the Magic Circle firm’s merger with New York’s Rogers & Wells.

A Simpson spokeswoman did not immediately respond to a request for comment about Wahlquist’s departure for Wachtell, whose future beyond legendary cofounder Martin Lipton was covered by The Wall Street Journal back in 2011.