Sullivan & Cromwell and Alston & Bird were the top mergers and acquisitions (M&A) legal advisers in the financial services sector during the first half (H1) of 2026 by value and volume, respectively, according to the latest legal advisers league table by GlobalData, which ranks legal advisers by the value and volume of M&A deals on which they advised.

Based on its Financial Deals Database, the leading intelligence and productivity platform revealed that Sullivan & Cromwell achieved the leading position in terms of value by advising on $24.9 billion worth of deals. Meanwhile, Alston & Bird led in terms of volume by advising on a total of 23 deals.

Aurojyoti Bose, Lead Analyst at GlobalData, comments: “Alston & Bird was the top adviser by volume in H1 2025 and retained its leadership position by this metric in H1 2026, despite a year-on-year decline in the total number of deals advised by it.

“Similarly, there was a decline in the total value of deals advised by Sullivan & Cromwell in H1 2026 compared to H1 2025. However, it remained well ahead of its peers in terms of value. Sullivan & Cromwell also occupied the fifth position by volume with 16 deals.”

An analysis of GlobalData’s Deals Database reveals that White & Case occupied the second position in terms of value, by advising on $18.6 billion worth of deals, followed by Clifford Chance with $18.2 billion, Paul, Weiss, Rifkind, Wharton & Garrison with $16.9 billion, and Latham & Watkins with $16.7 billion.

Meanwhile, Kirkland & Ellis occupied the second position in terms of volume with 22 deals, followed by Simpson Thacher & Bartlett with 21 deals, and Latham & Watkins with 20 deals.