Virtru - Virtru is your data privacy force field, wrapping and protecting emails and files wherever they're shared. Easy-to-use data security software for business. People also askIs Virtru Hipaa compliant?
dmarcian - Safeguard your email from abuse
Paubox - Paubox provides HIPAA compliant email encryption without the hassle of extra steps.
Proofpoint - Proofpoint provides cloud-based email security, e-discovery and compliance solutions for companies to protect sensitive business data.
Proofpoint Email Encryption - As email is the preferred medium for business communications, preventing confidential information from being leaked in outbound email messages must be a top priority in order to lower the risk of a data breach.
Barracuda Email Protection - Barracuda Essentials offers advanced Office 365 security features including email scanning, archiving, backup & recovery, and real-time phishing defense.