Salesforce said Wednesday that it officially closed its blockbuster US$27.7 billion acquisition of collaboration app Slack as the San Francisco tech giant aims to enter the work-from-anywhere technology arena. Slack said in a filing with the U.S. Securities and Exchange Commission on July 16 that the U.S. Department of Justice had closed its antitrust investigation into the acquisition. The companies announced the acquisition in December. “Together we’ll define the future of enterprise software, creating the digital HQ that enables every organization to deliver customer and employee success from anywhere,” Salesforce CEO Marc Benioff said in a statement. Slack CEO and co-founder Stewart Butterfield will continue to lead the new subsidiary within Salesforce.