In March 2018, Google announced that it had partnered with the Pentagon on an initiative known as "Project Maven" to help it analyze and interpret drone videos via artificial intelligence. In response, over 4,000 Google employees signed a letter calling on Google to cancel Project Maven and to draft, publicize and enforce a clear policy stating that neither Google nor its contractors will ever build warfare technology. A dozen employees also quit the company in protest. Following this opposition from employees, in early June 2018, Google announced that it will stop working on Project Maven when its current contract expires.