Susquehanna International Group, one of the largest options trading firms on the planet, is claiming it got fleeced. The firm has filed a lawsuit in Manhattan federal court alleging that anonymous traders used insider knowledge of an impending Chinese regulatory crackdown to rake in more than $100 million in options profits, leaving SIG holding the bag for over $70 million in losses.
The case names 100 John Doe defendants, which is legal speak for “we know someone did this, we just don’t know who yet.” And SIG is pulling every lever it can to find out.
What actually happened
On May 22, 2026, the Chinese government dropped a regulatory hammer on cross-border brokerages. New rules targeting firms operating across borders sent shockwaves through the sector.
According to SIG’s complaint, unidentified traders purchased roughly $12 million worth of options linked to Chinese securities firms shortly before the crackdown was announced. Those positions, which primarily consisted of put options (bets that prices would fall), exploded in value once the news broke.
