GreatHorn

GreatHorn was a cloud communications security company that built an email security platform designed to stop phishing, spear phishing, business email compromise, impersonation and credential-theft attacks. Rather than sitting in front of the mail flow as a gateway, the product integrated directly into cloud email platforms such as Microsoft Office 365 (natively via the Azure marketplace and O365 APIs) and Google's cloud email, so that detection and remediation happened inside the mail platform without introducing message delays during an attack.

The company positioned its approach as "active defense": removing or neutralizing attacks at the point they occur instead of only reporting on them, and explicitly not relying on changing end-user behavior as the primary enforcement mechanism. Later descriptions of the technology cite the use of artificial intelligence and machine learning to analyze email content and context for threat detection and response across cloud mailboxes. In August 2022 Proofpoint signed a definitive agreement to acquire GreatHorn, and the technology and leadership team were folded into Proofpoint's threat protection portfolio.

Founding story

GreatHorn came together in the year preceding its March 2016 seed announcement as a bet by CEO Kevin O'Brien and co-founder Ray Wallace on the convergence of two trends: rapid enterprise adoption of cloud infrastructure for core services such as email, and a parallel rise in data breaches originating through those channels, with most breaches beginning as highly targeted phishing attacks. O'Brien had previously been a product marketing director at cloud security company CloudLock.

Business model

GreatHorn sold its email security platform as a subscription service to organizations, charging on a per-mailbox, per-month basis.

Recurring per-mailbox, per-month subscription pricing for the cloud email security platform.

Traction

Approximately 10 employees are reported for the entity; the company raised a total of $8.55 million across disclosed seed and Series A rounds before being acquired by Proofpoint in 2022.

Latest developments

Proofpoint signed a definitive agreement to acquire GreatHorn on August 29, 2022, adding GreatHorn's cloud-native email security capabilities to Proofpoint's advanced threat protection platform. Former GreatHorn leaders, including co-founder and CEO Kevin O'Brien (SVP & GM, Email Security Products), took product, engineering, marketing, sales and customer success roles within Proofpoint's threat protection organization.