ReclaimTheNet.org notes that a recent change to Twitter’s terms of service adds that the company “may also remove or refuse to distribute any Content on the Services, limit distribution or visibility of any Content on the service…”
Twitter does not clarify what content may be subject to “limited distribution or visibility” giving the company free rein to limit any content it sees fit. In January 2018, an undercover report from Project Veritas showed a former Twitter engineer named Abhinav Vadrevu appearing to admit that Twitter uses shadow banning to limit the reach of content on its platform. “So they just think that no one is engaging with their content, when in reality, no one is seeing it,” Vadrevu stated.