Trader opens $2.31 million S&P 500 short and buys 8,400 Fed hold contracts

A trader opened an S&P 500 short position worth about $2.31 million on Hyperliquid and bought 8,400 contracts betting that the U.S. Federal Reserve will leave interest rates unchanged in October on Polymarket.

China-based BlockBeats reported, citing TradingBeats data, that a trader known as “ps5” opened new positions on both platforms. The trades took place between the previous night and the day of the report.

On Hyperliquid, the trader opened 300 contracts betting on a decline in the S&P 500. At the time of the data snapshot, the position was valued at $2,317,100, with an unrealized loss of about $1,140. TradingBeats identified it as the account’s only contract position.

On Polymarket, the trader bought 8,400 “Yes” contracts for $7,812 on the outcome that the Fed would hold rates in October. The purchase price implied a 93% probability of a hold, while the contract price at the time of the snapshot indicated a 95.85% probability. The remaining contracts had an unrealized gain of about $211.

The two positions are tied to different outcomes: one to a decline in the S&P 500 index, the other to the Fed’s rate decision. Prices of prediction market contracts express implied probabilities based on trading prices and are not official Fed decisions.

The Fed raised its benchmark interest rate by 0.25 percentage points in September, setting the target range at 3.75% to 4.00% a year. The upcoming policy meeting is its first since that increase. The meeting is scheduled for the 27th and 28th (local time), with the policy announcement set for 03:00 KST on the 29th.