PARIS: Google is set to invest in secure messaging start-up Symphony, primarily used by major financial entities and valued at $650 million, the Wall Street Journal said on Tuesday. Symphony uses encryption technology, allowing firms to communicate securely on a centralised platform. Neither Google nor Symphony commented on the report. Symphony launched globally last month as a rival to more expensive terminals from financial information provider Bloomberg, whose services are used by finance professionals and investors, who typically pay several thousand dollars a year for service.