Investment SoftBank has chosen another flashy investment: Slack September 18, 2017 johorbiznet Johor News SoftBank has chosen another flashy investment: Slack Recode Slack is now worth over $5 billion after $250 million cash injection led by Japan’s SoftBank CNBC Slack valued at more than $5B after Softbank investment New York Post Slack valued at $5bn after SoftBank joins fundraising Financial Times Full coverage Source: Investment New Feed