The Department of Justice’s Antitrust Division has opened an investigation into whether rent-setting software made by a Texas-based real estate tech company is facilitating collusion among landlords, according to a source with knowledge of the matter.ProPublica found the software is widely used in some markets: In one downtown Seattle ZIP code, 70% of more than 9,000 apartments were controlled by just 10 property managers — every one of which used RealPage’s pricing software in at least some of its buildings.“The focus of the investigation was ‘talk to competitors, talk to large rental companies,’” said the paralegal, who did not want to be named because she was not authorized to speak about the investigation.The investigation fell at a time when the DOJ’s Antitrust Division was preparing to sue to block a proposed merger between AT&T and Time Warner, which promised to take up a lot of the division’s resources.Klobuchar’s recent letter to the DOJ mentioned the 2017 merger, saying that such consolidation can make markets “more susceptible” to collusion and encouraging the department to consider looking at RealPage’s past behavior to see if any of it was anticompetitive."