Just dug into something wild about Jane Street—you know, that super secretive trading firm that barely anyone talks about until they're in legal trouble? Yeah, them.

So here's the thing that blew my mind: a company with just 3,000 people made $20.5 billion in trading revenue last year. That's MORE than Citigroup's entire trading division ($19.8B) and Bank of America ($18.8B). Combined, they're crushing major banks with a fraction of the workforce. This isn't just efficiency—it's almost absurd.

What makes Jane Street so different? Well, they literally have no CEO. The place is run by about 40 senior traders who own the company and make decisions collectively. No hierarchies, no titles like VP or Managing Director—just owners running different desks. Everyone's compensation is tied to overall company profits, not individual performance. This means nobody's taking crazy risks for their own bonus because losses hurt everyone equally.

Their recruitment strategy is equally wild. They don't care if you have a finance background or can code. They literally ask one question: Can you solve problems? An internship there pays $300k base salary for a 4-month contract. And the interview? Pure game theory and probability puzzles under pressure. Only a tiny percentage even make it to the interview stage.

Here's where it gets interesting though. Their core trading system runs on OCaml—a programming language almost nobody else in finance uses. As of 2023, their codebase hit 25 million lines of code. This creates an insane moat: engineers who learn OCaml at Jane Street can't easily jump to competitors because no other firm uses it. They're basically locked in by their own skill set.

But the real story? Jane Street has been caught in some serious legal battles lately. SEBI (India's SEC) investigated them for what looks like market manipulation in the Indian options market. According to a 105-page ruling, Jane Street allegedly used algorithms to buy massive amounts of index stocks right after market open, then sold them off before close to artificially tank prices—all while holding short positions in options. On one specific day, they lost $7.5M on spot trading but made $89M on options. Net profit: $81.5M. From January 2023 to March 2025, SEBI calculated Jane Street made about $4 billion total in India alone.

Then there's the Terra/Luna lawsuit. A Jane Street employee (Bryce Pratt) had been an intern at Terraform before jumping to Jane Street. He allegedly stayed connected through a private chat group. On May 7, 2022—the same day Terraform quietly withdrew $150M from Curve—Jane Street withdrew $85M from the same pool ten minutes later. Together they pulled $235M, which broke UST's liquidity support and triggered the collapse that wiped out $40 billion. The liquidators are now suing Jane Street, claiming insider trading. Jane Street's response? They called it "desperate extortion" and blamed Do Kwon's fraud.

Here's what fascinates me: Jane Street's alumni basically dominated the FTX collapse story. SBF worked there (2014-2017), Caroline Ellison (Alameda CEO) was a Jane Street trader, even SBF's brother worked there briefly. The density of that network is impossible to ignore.

What IS Jane Street exactly? They're simultaneously the most profitable trading firm on Wall Street, a master of exploiting information asymmetry at scale, and apparently someone willing to operate in some very gray legal areas. They describe themselves as "puzzle solvers," but when people started asking questions about Jane Street itself, they became the puzzle.

The wildest part? Their 2016 election night play. They built a system to predict election results faster than CNN using state-by-state voting data. When Florida data showed Trump surging from 5% to 60% odds around midnight, they shorted the S&P 500 with positions worth several billion dollars—betting on a market crash. By the time SBF went to sleep, they had a $300M paper profit. Three hours later? The market had priced in Trump and started rallying. Their short positions got squeezed. That $300M profit turned into a $300M loss overnight. A $600M swing in hours. Jane Street didn't punish SBF for the loss—they actually praised his forecasting system's accuracy. The mistake was in predicting market psychology, not math.

This company exists in this weird space where they're simultaneously genius engineers, ruthless profit-maximizers, and apparently comfortable with strategies that regulators around the world are now questioning. Whether you see them as visionary market infrastructure or something darker probably depends on which side of their trades you were on.