Collusion among enterprises can restrict market competition, and anti-monopoly laws in various countries all regulate collusion. Collusion is divided into explicit collusion and tacit collusion: The former stresses mental connection or information exchange among operators, which can be proved by direct evidence; the latter refers to actual coordinated actions among operators without explicit and perceivable agreements and connections, which mostly occurs in oligopoly markets. The monopoly agreement system once constituted the main legal basis for tacit collusion, but it is difficult to prove the mental connection in tacit collusion that is the basis of identifying monopoly agreement. Based on this, the European Union introduced the collective dominance system. This approach solves the problem of proof of mental connection under the monopoly agreement system. However, there are controversies over why several operators are identified as a whole to prove the existence of collective dominance, and what standards should be satisfied to identify the existence of such collective dominance.The collective dominance system has its unique value in the digital era. On the one hand, the digital market features high concentration, and the higher the market concentration, the more likely operators are to coordinate their actions by tacit collusion. On the other hand, even if the oligopoly market has not yet emerged, the combination of algorithms and big data also makes the market more transparent. Accompanied by the continuous development of predictable and autonomous algorithms, and the gradual improvement of virtual supervision and punishment mechanisms, it is easier for operators in the digital market to conduct consistent acts. When it is difficult to prove monopoly agreements, the collective dominance system matters in solving the tacit collusion among enterprises in the digital era.However, the application of the collective dominance system is facing the confusion of identification standards in China: The Anti-Monopoly Law fails to establish special standards for the identification of collective dominance, and in practice, the anti-monopoly enforcement agencies also presume and identify collective dominance in a too simple manner. The concept of collective dominance originates from the EU that regards “economic links” and “market structure” as the main standards for identifying collective dominance through case law. But in different cases, identification standards are different, and the opinions of the European Commission and the courts are not consistent. The standards for identifying collective dominance can be divided into two classes: the identification of “collective” and the identification of “dominance”. Then the two classes can be divided into four elements: There is a specific market environment or economic links that are conducive to the conduct of consistent acts by operators; operators form a whole by conducting consistent acts so that they can be regarded as a collective entity and regulated under the single dominance system; operators have integrated anti-competitive consciousness to conduct consistent acts; and the whole can behave independently of competitors, customers and consumers.