The de facto merger doctrine refers that, when an asset acquisition leads to the same result as a statutory merger, which avoids the protection procedures of shareholders and creditors, these transactions are demanded to be constrained by the same rights as in the statutory merger. Based on the concept of the fair treatment of stakeholders in the same transaction, the de facto merger doctrine was born to protect the evaluation of dissident shareholders. After the implementation of shareholder protection, the jurisprudence began to apply the doctrine to the field of creditor protection and incorporated it into the scope of successor liability. Subsequently, the scope of application of successor liability arising from substantive mergers is expanding, including in the area of product liability, environment and labor and personnel matters. In recent years, the court's application of the doctrine does not mechanically ues four elements of de facto merger doctrine, but rather analyzes the purpose and effect inherent in the transaction based on specific facts, and its flexibility is greatly enhanced. Clarifying the rules of the US de facto merger doctrine will help to draw lessons for Chinese enterprises doing “going out” asset acquisition transactions overseas and reduce the risk of overseas mergers and acquisitions.