Regulations Governing the Conduct of Securities Trading Margin Purchase and Short Sale Operations by Securities Firms Article 18

In the event that a customer of a securities firm fails to pay the maintenance margin in accordance with the provisions of paragraph 1 of the preceding Article or fails to settle the transaction within the agreed time limit, the securities firm shall dispose of the collateral. However, this rule does not apply if otherwise stipulated between the parties.
中文原文 證券商辦理有價證券買賣融資融券管理辦法第18條
證券商客戶未能依前條第一項規定補繳差額,或逾約定期限未能清結時,證券商應即處分其擔保品。
但雙方另有約定者,不在此限。

English translation for reference only; the Chinese text prevails. Not legal advice.