Yesterday evening, ACT plummeted by over 50% within a few minutes on Binance's perpetual contract market, triggering a market chain reaction. Although initial suspicions pointed to market maker Wintermute, subsequent investigation revealed that the true catalyst was Binance's sudden adjustment of contract leverage and margin system, causing large investors to be forcibly liquidated and engage in surrender-like sell-offs. Yesterday evening, ACT experienced a sharp drop of over 50% in Binance's perpetual contract market, becoming the biggest victim of this adjustment. Tokens like DEXE and DF also saw steep declines of 23% and 16% respectively. On X platform, many traders initially blamed market maker Wintermute for large-scale selling, but the company's CEO Evgeny Gaevoy quickly denied this, stating that their selling was a passive response to price decline. Trader @CnmdRain pointed out that the leverage multiples and margin levels for tokens like ACT on Binance were suddenly lowered yesterday, directly impacting existing positions. More controversially, this change was only communicated to the market less than three hours in advance, leaving traders and market makers using high leverage with almost no room to respond. He explained that ACT's price crash primarily stemmed from forced liquidations after rule adjustments, resulting in $27 million worth of sell orders in a short time. Notably, one whale holding ACT was liquidated from a $3.79 million position, indirectly triggering a series of sell-offs. The price crash simultaneously created a price difference between contracts and spot markets, attracting arbitrage bots that bought contracts and sold spots, further intensifying selling pressure. Former FTX community manager Benson Sun directly stated: "Before changing rules, Binance should first assess how many positions would be affected and provide early notification to market makers with large positions." In a subsequent investigation report, Binance stated that this phenomenon resulted from three VIP users collectively selling $510,000 and one non-VIP user selling $540,000, causing significant volatility in a low-liquidity market. Formula News disagreed, pointing out that the report only examined spot market trading data, while the massive sell-off was actually triggered by perpetual contract market sales. They noted that multiple ACT large investors who had maintained high positions to support the price chose a surrender-like sell-off under the double impact of no buyers and sudden rule changes. Large investors opted to dump all at once to attract liquidity and reduce overall losses, rather than using a TWAP strategy to prevent other short sellers from escaping first. DWF Labs founder @ag_dwf commented on the simultaneous decline of multiple unrelated tokens as "unusual" and promised to provide financial support to help affected projects recover.

If your project is affected by this incident, please contact us. We will allocate funds for repurchase and develop a recovery plan for your token.

Wu Blockchain's chief editor Colin Wu pointed out that since Binance has strengthened restrictions on active market makers, the market may lose part of its liquidity support, and the vulnerability of small-cap tokens will be magnified, making similar flash crash events potentially become the norm.

Just this morning, significant short-term price drops were indeed observed on tokens such as MASK, LEVER, and KAVA, inevitably raising concerns about whether there will be another wave of sharp declines.

Crypto Market Structure Faces Another Test

This flash crash of ACT reflects the profound impact of leverage systems on market stability, and highlights that policy changes without buffer and communication can easily trigger market chain reactions. For exchanges, transparency and risk control mechanisms will be key to gaining market trust in the future.