The battle for control of Warner Bros. Discovery has become the defining corporate deal of 2025, concentrating an unprecedented level of Wall Street talent. As Netflix and Paramount fight for the media giant, eight of the year's top 20 mergers and acquisitions bankers are advising one side or the other, according to the annual Rainmakers ranking by Business Insider and MergerLinks.

The list, which ranks North American investment bankers by the total value of deals they led in the prior year, reveals a significant rebound in global M&A activity. The world's top dealmakers accounted for a major share of the $4.6 trillion in worldwide transactions announced in 2025, a staggering 50% increase from the year before, data from industry tracker LSEG shows.

New Faces and Firm Reshuffles

This year's ranking is marked by significant churn, with nine bankers appearing for the first time. It also highlights the rising fortunes of Wells Fargo, a retail-focused lender that has recently made competitive inroads in investment banking. The firm, which saw a strict government asset cap lifted last year, jumped from 17th to 9th place in the global M&A advisory league tables.

This surge was clinched by a major 2025 win: Wells Fargo serves as the primary advisor to Netflix on its proposed takeover of Warner Bros. Discovery. The bank's star recruit, Michael Hogan, who joined from Morgan Stanley in May 2023, makes his inaugural appearance on the Rainmakers list with $153.4 billion in total deal value.

The Contenders for a Media Titan

The competing bid for Warner Bros. Discovery, from Paramount, is represented by another first-time rainmaker: Gerry Cardinale, founder and managing partner of RedBird Capital Partners. His firm, which manages around $14 billion in assets, has made high-profile investments in Skydance Media and Italian football club AC Milan.

Further intensifying the deal's significance, veteran banker Michael Klein, now running his own boutique firm M. Klein & Co., also joins the list for the first time thanks to his advisory role in this "most contentious megadeal."

Established Leaders Maintain Dominance

Despite the influx of new names, established figures from bulge-bracket banks retained top positions. Anu Aiyengar, JPMorgan Chase's global head of advisory and M&A who topped last year's list, returns after helping steer the firm to over $1.2 trillion in total deal value. Goldman Sachs veterans also feature prominently, with Sam Britton and Timothy Ingrassia helping the firm retain its number one position in the annual M&A league table.

The ranking methodology, managed by UK-based MergerLinks, tracks publicly announced deals and calculates values on a net basis, including both equity and debt. To qualify, a banker must have been the lead advisor to one of the transaction parties.

Key Data from the 2025 Rainmakers List:

Michael Hogan (Wells Fargo): Ranked #1 with $153.4bn in deal value. The former Morgan Stanley tech banker has been a primary architect of Wells Fargo's meteoric rise in advisory rankings.

Anu Aiyengar (JPMorgan Chase): Ranked #8 with $105.2bn. She has advised on more than a trillion dollars' worth of deals and is considered one of the financial services industry's most influential female leaders.

Gerry Cardinale (RedBird Capital): Ranked #13 with $94.7bn. The former Goldman Sachs partner founded his investment firm in 2014, focusing on sports, media, and financial services.

Global M&A Volume: Surged to $4.6 trillion in 2025, a 50% increase from 2024, driven by large, strategic tie-ups.