Newer/trending anti-phishing/fraud products REQUIRE a cloud based messaging system (M365, Google apps, etc.). For example, we are a Trend ScanMail for Domino customer. We cannot use enhanced security products such as Barracuda's Sentinel, or offerings from Mimecast, as they are geared toward non-Notes/Domino deployments. Use some marketing funds and work with them if you see the point for product development. If M365 and Google Apps have all the ancillary market and ecosystem, its because the ISVs are writing/creating their stuff for the market. Make the market. Mimecast's product, for example, has Outlook plugins.