Jane Street made it's way into today's Wall St Journal for its quantitative prowess and hiring of Math PhD's. What was stunning to hear was that their 2nd quarter profits were a record $10.3 billion, nearly double that of Goldman Sachs and Morgan Stanley (much larger firms).
They made money through extreme manipulation of the Indian stock market...when working with a market that has 422X leverage through derivatives its much easier to make money.
Market-making in a market that is highly speculative and illiquid isn’t the same as market manipulation though.
They're a trading firm that hires really clever people to use math to trade. Their strategies are, presumably, very complicated and ever changing, and secrecy about them is the point - you get bigger margins for longer if people don't learn about your 'one weird trick' (that and also that there is presumably another side to your trades losing out on upside, and they might not be best pleased to learn about it.
> really clever people
Sam Bankman-Fried and his League of Legend rankings would like a word
One trick is buy low sell high, apparently only a few know about this.
They’re a market maker
manipulate foreign equity markets
Print money?
Governments print money, high frequency traders extract money. They would say that they provide liquidity to the market as a service.