Fortunately Signal is a well funded non-profit which reduces the likelihood of its acquisition significantly.
"[...]use the Services to store or transmit any inappropriate content, such as content that: (i) contains unlawful, defamatory, threatening, abusive, libelous or otherwise objectionable material of any kind or nature" [1]
(My emphasis)
1) we use it as a slack replacement 2) git integration 3) stellar Blockchain payments 4) encrypted file sharing 5) great system for key management