Softbank has ploughed more cash into another "unicorn" startup, this time, Slack.
The Japanese form's Vision Fund has led a $250m investment in the US tech firm which values it at $5bn. Accel, an early investor, also joined the series G round.
The spending spree follows recent cash for WeWork, the co-working space startup, talk of an investment in either Uber or Lyft, and cash for Ola and Didi, ride-hailing giants in India and Asia - all of them valued at more than $1bn.
The spending spree gives Softbank's massive $100bn fund, backed by the likes of Apple, Qualcomm, Foxconn and Saudi Arabia's sovereign wealth fund, a stake in several of the most highly-valued private technology companies in the world.
Slack said the fresh cash, which brings the total it has raised to $841m, is not even necessary and will add to its existing capital as it heads toward becoming cash-generating, but gives it long term backing.