GigaDevice Semiconductor (03986) shares plummeted 5.31% in intraday trading, reaching a new low, as investors reacted to the disclosure of a major share sale by the company's chairman.

The selloff was triggered by the announcement that shareholder Zhu Yiming disposed of a total of 11.11 million A shares, representing 1.58% of the company's total issued shares, between May 6 and June 12. The sale prices ranged from 339.44 yuan to 538.90 yuan per share, with total proceeds amounting to approximately 4.4 billion yuan. This significant reduction in holdings by a key insider weighed heavily on market sentiment.

Although the company later announced a series of confidence-boosting measures, including a planned 1 billion yuan share purchase by the chairman and a proposed buyback, the immediate impact of the cash-out drove the stock sharply lower.