Jane Street Tops Asian Block Trading After Segantii Exit

Jane Street has emerged as one of the leading buyers of large share blocks in Asia following the 2024 closure of hedge fund Segantii, according to people familiar with the firm’s activities. Banks and trading desks arranging large equity disposals now frequently approach the New York-based proprietary trading firm as a potential buyer.

Block trades are large, privately negotiated sales of shares. Buyers can obtain shares at a discount to the market price while sellers can move sizable stakes in a single transaction without putting equivalent pressure on the open market.

Data from Dealogic shows total block sales across Asia exceeded $48 billion in both 2024 and 2025. India accounted for the largest share of that activity, followed by Hong Kong and Japan.

People familiar with the operations say Jane Street’s capacity to hedge market exposure and hold positions for longer periods than many hedge funds has helped its rise in the block-trading market. The firm’s growing balance sheet and the scale of its proprietary trading business allow it to warehouse positions rather than immediately offload risk to other market participants.

Segantii, which had been a major presence in Asian block trading, shut down in 2024 after its founder, Simon Sadler, was charged with insider dealing. Sadler has pleaded not guilty and is on trial in Hong Kong over allegations he traded in shares of Esprit ahead of a block sale.

Before Segantii’s exit, Jane Street had participated in Asian block trades but was not considered a top-tier buyer. Market participants say the combination of Segantii’s departure and Jane Street’s capital and risk capacity has shifted counterparties’ preferences toward the firm.

Regulatory scrutiny of block trading increased after the events surrounding Segantii, and banks and brokers have become more cautious when choosing counterparties. Deal teams have sought buyers with substantial capital and risk-management capabilities.

Jane Street’s expansion in Asian block trading has faced setbacks. The firm recorded its first monthly loss in a decade in July after a sharp sell-off in stocks linked to artificial intelligence affected some positions. Participation by large proprietary traders is difficult to quantify because many block transactions are negotiated privately and not publicly disclosed; industry data provides a partial snapshot.

The Asian block-trading market has grown into a multibillion-dollar segment of equity capital markets, driven by steady deal flow across major markets and by sellers’ need to execute large disposals without immediate market impact.