David Solomon, CEO of Goldman Sachs (L), Jamie Dimon, CEO of JP Morgan (C), and Ted Pick, CEO of Morgan Stanley.

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Fueled by the global boom in artificial intelligence stocks, relaxed capital rules and greater lending to hedge funds, big Wall Street banks have already had a banner year for equities trading — even with one quarter left to go.

The five biggest investment banks have generated about $67 billion in equities revenue through Sept. 30, according to company filings. That is $7 billion more than what the group made during all of 2025, which itself was a record haul.

But it's Wall Street's Big Three that have captured the largest slice of what is shaping up to be the industry's most lucrative arena: Goldman Sachs , JPMorgan Chase and Morgan Stanley have made a combined $52 billion in stock trading revenue so far this year, nearly 80% of the total.

"When it comes to the AI mega trade, the Big Three consider each other their main competitors, and that's pretty much it," Mike…