What is "acting in concert"?

The cooperation of investors in achieving identical investment objectives, both formal and informal. This can occur, for example, during an acquisition where a group of investors works together. A reporting obligation to the regulator often applies, depending on the regulations in the country or market concerned. In the Netherlands, there are rules regarding the cooperation of activist shareholders who jointly implement a voting policy to influence a company's policy. In some cases, however, 'acting in concert' is prohibited, such as in the case of price manipulation.