The company that secures the devices no one else can see - the printers, controllers, sensors and medical pumps that can't run a security agent.
San Jose, California - The Forescout logo, photographed against the navy of a network operations center. Founded 2000, headquartered on Santana Row, roughly 1,000 employees across four continents.
Most security tools assume you already know what's on your network. Forescout assumes you don't - and that assumption is usually correct. Enterprises routinely undercount their connected devices by a wide margin, and the ones they miss are exactly the ones attackers find first: an unmanaged printer, an aging industrial controller, a networked infusion pump, a rogue laptop that joined the guest Wi-Fi an hour ago.
Forescout's platform discovers and classifies every device the moment it touches the network, without requiring any software - an agent - to be installed on it. That agentless approach is the whole point. You cannot install security software on a 20-year-old programmable logic controller or an MRI machine, but you can watch how it behaves on the wire. Once a device is seen and identified, Forescout can enforce policy: grant or restrict access, segment it away from sensitive systems, check it for compliance, and trigger a coordinated response through the other tools already in the security stack.
The result is a continuously updated map of the entire cyber-asset estate - IT laptops and servers, operational technology (OT) on factory floors, the broad category of Internet-of-Things (IoT) devices, and the Internet-of-Medical-Things (IoMT) inside hospitals - all under one roof.
Roughly 3,200 organizations rely on Forescout, including about one in five Fortune 500 companies and numerous government and federal agencies. The strongest fit is in financial services, healthcare, manufacturing, utilities and energy, aerospace and defense, automotive, retail and the public sector - anywhere large heterogeneous device fleets meet regulatory pressure.
As IT, OT and IoT converge, the attack surface has exploded with devices that traditional endpoint tools simply ignore. Forescout closes that blind spot - inventorying the unknown, segmenting the risky, and enforcing zero-trust access on devices that were never designed with security in mind.
The unified platform (renamed from the 4D Platform) for asset visibility, access control, segmentation, threat detection and exposure management across IT, OT, IoT and IoMT - powered by agentic AI.
The original agentless discovery engine that classifies every device the instant it connects - still the foundation of the platform.
Policy-based access enforced via 802.1X, MAC authentication bypass and API actions through switches, controllers and firewalls - including BYOD and OT/IoT.
Maps real traffic flows and enforces zero-trust segmentation so a compromised device can't reach what it shouldn't.
Deep-packet monitoring and threat detection built for industrial control systems and operational-technology networks.
Bi-directional integrations with 180+ SIEM, EDR, ITSM and IT tools so the whole security stack responds as one system.
An agentic AI layer that adds proactive, autonomous capabilities to threat and exposure management.
Forescout's in-house threat-research team, specializing in IoT, OT and IoMT, publishing the annual Threat Roundup and feeding device intelligence into the platform.
The rapid expansion of connected, aging devices across IT, IoT and OT environments creates unprecedented risk - and we are laser focused on tackling these challenges together with customers.
The cyber-physical security market has strong specialists - Armis, Claroty, Nozomi Networks and Dragos in OT and IoT; Cisco and Microsoft with adjacent platforms. Forescout's distinguishing bet is breadth without lock-in: one platform that spans IT, OT, IoT and IoMT, discovers devices without agents, and stays deliberately vendor-agnostic by integrating with 180+ other tools rather than replacing them.
Where many rivals started in a single niche, Forescout has spent 25 years on the unglamorous discipline of complete discovery - the belief that segmentation and zero trust are only as good as the inventory beneath them.
Forescout sells subscription and license access to its platform and modules, plus support and services, to large enterprises, critical-infrastructure operators and governments - through both direct sales and a global channel of partners. Add-on modules and integrations expand revenue across a customer's device estate.
Forescout sits at the intersection of network access control and the fast-growing market for cyber-physical systems (CPS) protection - the same space Gartner formalized with its first CPS Magic Quadrant in 2025. Its edge is spanning the IT/OT divide most competitors sit on one side of.
Launched with roots in San Jose and Tel Aviv around agentless device visibility; original product named CounterACT.
Goes public as FSCT, raising about $116M at $22/share, valued above $800M.
Adds eyeInspect for OT/ICS monitoring and eyeSegment for network segmentation.
Advent International and Crosspoint Capital acquire Forescout in an all-cash deal.
Consolidates threat research into a dedicated IoT/OT/IoMT intelligence team.
Multiple industry awards, quantum-safe encryption detection patent, and an 84% rise in OT-protocol attacks reported.
Renames the platform to Forescout Vistaro and introduces VistaroAI.
It provides a cybersecurity platform that agentlessly discovers, classifies, secures and monitors every device on a network - across IT, OT, IoT and IoMT - and enforces access control, segmentation and compliance.
Agentless means Forescout identifies and controls devices without installing software on them, by watching the network. That's essential for devices like industrial controllers, medical equipment and IoT sensors that can't run traditional security agents.
It has been privately held since 2020, when Advent International and Crosspoint Capital Partners acquired it in a $1.9 billion take-private deal. It previously traded on NASDAQ as FSCT after its 2017 IPO.
Armis, Claroty, Nozomi Networks, Dragos, Cisco, Microsoft (Defender for IoT), Ordr and Portnox, across the network access control and cyber-physical systems security markets.
Vistaro is Forescout's unified platform, renamed from the 4D Platform in 2026. It combines asset visibility, access control, segmentation, threat detection and exposure management, enhanced by Vedere Labs intelligence and VistaroAI agentic AI.