$868 Moves $500M SK Hynix Futures Market, The Truth Behind the Hyperliquid Wick

Written by: 0xFacai, Lawt

Under thin liquidity, real transactions do not equal reliable prices.

On the morning of July 28, 2026, only one share of SK Hynix was traded in the Korean pre-market at 1,272,000 KRW, approximately 868 USD.

This transaction of less than 900 USD was subsequently fed into TradeXYZ's pricing system, causing the SKHX perpetual contract to drop from a low of 1,128.2 USD to 927 USD within one minute.

In less than three minutes, hundreds of accounts were taken over by the system. In the following four hours, the liquidation scale rose to approximately 80 million USD.

868 USD leveraged the Hyperliquid Hynix perpetual contract market with an open interest of 500 million USD.

Korean Stock Pre-Market Pricing

The incident originated at Nextrade, also known as NXT, an alternative trading system operating outside of KRX in Korea.

NXT pre-market uses continuous auction. If the buy price is higher than the sell price, the order is executed immediately.

It does not depart from the price limit restrictions of Korean stocks; the price upper and lower limits are still based on the previous trading day's KRX closing price, with a range of approximately 30%.

SK Hynix's closing price the previous day was approximately 1,816,000 KRW.

Calculating 30% downward and adjusting according to the minimum quotation unit for Korean stocks, 1,272,000 KRW falls exactly near the legal price lower limit.

This transaction did not violate market rules. The problem lies in order book depth: NXT pre-market buy orders were very thin, so a sell order with a low enough price executing only one share pushed the latest transaction price to the lower limit.

Source: @yourquantguy

Whether the seller made an operational error, intentionally suppressed the price, or was simply willing to sell at that price, there is currently no evidence to confirm.

For subsequent liquidations, subjective intent is actually not that important.

It was a real transaction and fell within the allowed price range, so external market systems had reason to accept it.

The danger started here.

The Transmission Chain of Mispricing

According to TradeXYZ's official documentation, SKHX tracks the USD value of one share of SK Hynix common stock.

The calculation method is straightforward: the KRW price of 000660.KS divided by the USDKRW exchange rate yields the SKHX oracle price.

TradeXYZ divides Korean stocks into external oracle feed and internal pricing periods.

Korean time 8:00 AM to 8:50 AM belongs to the pre-market external pricing period, corresponding to Beijing time 7:00 AM to 7:50 AM.

This means that as soon as NXT starts pre-market trading, TradeXYZ will obtain executable quotes from institutional data providers and use them as external price inputs.

Before 7:00 AM Beijing time, SKHX was still in the internal pricing phase, and the oracle mainly adjusted slowly based on the impact price of TradeXYZ's own order book.

Once 7:00 AM arrives, external data resumes, and the oracle will revert to external prices at the next update.

This switch coincided exactly with the single-share transaction at 868 USD.

According to on-chain records, at 07:00:21.678, TradeXYZ's "Oracle Update Component" submitted an update to HyperCore: SKHX's external price was 868.17 USD, oracle price was 908.21 USD, and the two "Mark Price Components" were 921.96 and 954.98 USD respectively.

The "Mark Price" is the price that TradeXYZ presents to users and actually uses.

TradeXYZ takes the median of three numbers: the oracle price; the oracle price plus the 150-second EMA of the perpetual contract mid-price deviation relative to the oracle; and the median of the best bid, best ask, and last trade price on the order book.

This design incorporates TradeXYZ's order book and time smoothing mechanisms, which can delay abnormal price transmission, but did not anticipate a hidden risk deeper down: external pricing may also rely on a market with insufficient liquidity.

Within one minute at 07:00 AM, SKHX opened at 1,128.2 USD, touched a low of 927 USD, contract trading volume reached 40,978 (contracts), generating a total of 7,501 transaction records.

The ±10% boundary used during the internal pricing period to limit price discovery did not stop this decline either, because external pricing had resumed, and the system's reference anchor switched to the new external price.

Liquidations Flowed from Traders to System Accounts

Liquidation figures need to be divided into two categories.

According to HyperInsight's transaction-by-transaction statistics on on-chain addresses, the SKHX liquidation notional amount was approximately 79.398 million USD in a short period, open interest dropped from 481 million USD to 331 million USD, a decrease of approximately 150 million USD.

The top three addresses on the liquidation list were liquidated totaling 14.7754 million USD, among which the address starting with 0x320, which suffered the largest loss, was liquidated approximately 3.957 million USD, realizing a loss of approximately 2.045 million USD.

In this liquidation, approximately 26.26 million USD flowed to a special address: 0x4000000000000000000000000000000000000001.

From 07:00:21 to 07:00:48, it took over 406 long accounts, totaling 27,098.687 SKHX contracts, with a weighted average price of approximately 969.05 USD.

The liquidation process usually sends forced liquidation orders to the order book first.

If market buyers can absorb the sell orders, positions are closed in the open market; if the order book cannot execute in time and account margin continues to deteriorate, the system must transfer the remaining positions out.

0x400...0001 assumed the role of backstop and liquidation intermediary in this incident.

It passively became long.

The takeover did not end the risk.

After the price continued to fall, on-chain records began to list 0x400...0001 itself as a liquidated account.

A total of 26,560.549 long positions from this address entered the next wave of liquidation, corresponding to a transaction notional amount of approximately 24.7374 million USD, realizing a loss of 1.001 million USD.

There is also a documentation issue here.

TradeXYZ's public page still states that XYZ assets are not protected by the HLP Liquidator Vault and there is currently no backup liquidator; however, actual on-chain data marks these position transfers as backstop.

Therefore, 0x400...0001 cannot be directly equated to the HLP Vault.

A more conservative definition is that it is the system backstop account called by HyperCore during this SKHX incident.

Public documentation has not yet explained the relationship between this current process and the old version instructions.

Binance Gave Up One Hour of External Quotes but Escaped Unscathed This Time

The same Korean spot transaction also affected Binance's SK Hynix perpetual contract, but the result was much lighter.

High-frequency trader Boywus made a direct comparison between the two mechanisms: at 7:00 AM Beijing time, TradeXYZ on Hyperliquid had already accessed Korean pre-market external quotes; Binance remained in the internal pricing phase at this time, switching to external quotes only around 8:00 AM when the Korean main market opened.

Binance's official documentation shows that stock perpetual contracts use order book impact mid-price when external markets are closed, and use EWMA smoothing index, with purposes including reducing opening gap jumps and liquidation risk during low liquidity periods.

In the first minute at 7:00 AM, the SKHYNIXUSDT index only dropped from 1,132.49 USD to 1,130.66 USD;

TradeXYZ accepted earlier price discovery at 7:00 AM; Binance gave up this one hour of external quotes, losing some timeliness, but avoided the impact of 868 USD directly entering the liquidation system.

This has nothing to do with centralization or decentralization.

The difference merely comes from when external prices take over, whether the switching process is smooth, and whether liquidation prices have independent outlier protection.

Source: @Boywus

Given the Situation

Some may argue that TradeXYZ merely faithfully reflected real market conditions.

1,272,000 KRW was indeed traded, data providers did not report errors, and various modules of the trading platform transmitted the price on-chain according to established rules.

From this perspective, it is difficult to find a clear rule basis for compensation.

But correct price discovery does not mean reasonable liquidation design.

Traditional markets have long distinguished between the latest transaction price, index price, and fair price used for risk control.

The significance of the existence of the "Mark Price" is to prevent a single local transaction from directly determining the life or death of high-leverage accounts.

In this incident, although external quotes were limited by median, EMA, and update magnitude, they still triggered approximately 80 million USD in liquidations within one minute, indicating that existing protection mechanisms do not match the depth of the reference market.

Connecting to more quote providers alone cannot solve this problem.

Multiple data sources are observing the same NXT pre-market order book, single-share low-price transactions will enter their quotes simultaneously, and the median will ultimately still approach the same abnormal price.

Service providers are dispersed, but underlying liquidity is not.

Hyperliquid has handed over the oracle definition and operational responsibility for the HIP-3 market to the deployer, but liquidation is executed by HyperCore, so risk and reputation will not be limited to the HIP-3 deployer.

Earlier and broader price discovery has value, but also has costs; hopefully Hyperliquid and TradeXYZ can learn from this experience.