The four Big Tech companies -- Alphabet"s Google GOOGL.O, Amazon AMZN.O, Apple AAPL.O and Facebook FB.O -- face an array of antitrust investigations at the federal and state level which were revealed in mid-2019. While Democrats may be viewed as tougher on antitrust regulation, traditional Republican concerns about regulatory overreach appear to be overridden by anger over allegations that Big Tech tries to stifle conservative voices. These are the inquiries that are underway: Justice Department on Google: The U.S. Justice Department is expected to file a relatively narrow complaint within two weeks, which accuses Google of seeking to disadvantage rivals in search and in lucrative search advertising. Justice Department on Apple: This probe, which was revealed in June 2019, appears to focus on Apple’s app store. Some app developers have accused Apple of introducing new products and then pushing out apps which compete with them. Apple says it seeks to have only the highest quality apps in the app store. Justice Department on Facebook and Amazon: In July 2019, the Justice Department said that it was expanding its Big Tech probes to include “search, social media, and some retail services online” -- an apparent reference to Facebook and Amazon as well. Federal Trade Commission on Facebook: FTC officials probing Facebook have asked about past acquisitions, like Instagram and WhatsApp, and how Facebook treats app developers on its platform. The FTC told Facebook in June 2019 it was probing whether the company has engaged in unlawful monopolistic practices. Federal Trade Commission on Amazon: In its probe of Amazon, the FTC is likely looking at the inherent conflict of interest of Amazon competing with small sellers on its marketplace platform, including allegations that it used information from sellers on its platform to decide what products it would introduce. State attorneys probe Google: A group of state attorneys general led by Texas is expected to file a lawsuit focused on digital advertising, while a group led by Colorado is contemplating a more expansive lawsuit against Google that may also include concerns about its Android business. State attorneys general probe Facebook: New York Attorney General Letitia James, who leads the state attorneys general probing Facebook, has said that the investigation would look at whether the company’s actions endangered consumer data, reduced consumer choice or increased the price of advertising.