Lockheed: Mitigating Sonic Booms Critical To Making Supersonic Flight Economically Viable Written 27 August 2018

CNET News profiled the increasing amount of companies, which include Lockheed Martin, Aerion Supersonic, Spike Aerospace, and Boom Technology, who are working to design supersonic aircraft “cheaper, quieter and friendlier to the environment than Concorde while minimizing the troublesome effects of a sonic boom.” Lockheed is working with NASA on its X-59 QueSST Low-Boom Flight Demonstrator (LBFD), which Lockheed plans to first fly in 2021. According to Lockheed LBFD Program Manager Peter Iosifidis, “mitigating the effects of a sonic boom over land is critical to making supersonic flight economically viable.” 
More Info (CNET News)