This article has been reviewed according to Science X's editorial process and policies . Editors have highlighted the following attributes while ensuring the content's credibility: A sign for The Blackstone Group L.P. investment firm stands in front of their offices, Monday, Oct. 15, 2018, in New York. Credit: AP Photo/Mark Lennihan, File Private equity firms Vista Equity Partners and Blackstone are buying software maker Smartsheet for approximately $8.4 billion in cash. Vista and Blackstone said Tuesday ...