mark crumpton. this is bloomberg. david. david: word came yesterday that u.s. antitrust authorities have apparently divided of responsibility for new investigations of google, facebook, apple, and amazon. baer, now aill partner at arnoldcome. good to have you with us. >> nice to be on the show. david: we saw a pretty abrupt reaction in the market to these stocks, on the reports that they would start an investigation. let's take a step back. what is required before you start an investigation? if you are back at the department of justice, what do you need to find before you start an investigation? >> i used to work at the ftc as well. you have to have some good reason to believe something bad might be going on. , competitors, people downstream who buy the product will come in and complain. if that happens, you study a little bit, do some online research. you may want to open an investigation. because we have two antitrust agencies, federal trade commission, doj antitrust division, they have a clearance process. we have an issue we want to look at. according to the press reports we saw, there appears to have been a discussion about which of these very successful platforms to be looked at, and by which agency. that is the