CISO Tribune

Vendor comparison · 2 companies

Harmonic Security vs SquareX

Harmonic Security sells AI Governance and Control (AIGC), a control layer that secures and enables the AI-First workforce. SquareX sells a Browser Detection and Response (BDR) solution that organizations use to detect, mitigate and threat-hunt client-side attacks. CISO Tribune files both under Data loss prevention. This page sets the two records side by side: what each sells, where it is based, who owns and funds it, the customers it names and its recent news, each fact numbered to its source.

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  • Harmonic Security
  • SquareX
Harmonic Security vs SquareX: Products, Customers and Funding Compared
Harmonic SecurityHarmonic Security sells AI Governance and Control (AIGC), a control layer that secures and enables the AI-First workforce.harmonic.securitySquareXSquareX sells a Browser Detection and Response (BDR) solution that organizations use to detect, mitigate and threat-hunt client-side attacks.sqrx.com
What it sells
  • Harmonic Command[3]Gives security teams visibility into how employees and agents use AI, plus controls for using the tools safely.
  • MCP Gateway[2][3][4][6]A local gateway that extends Harmonic coverage to MCP activity.
  • Harmonic Endpoint Agent[6]Identifies native AI apps, IDEs, CLI tools, locally hosted models and inference API calls on employee devices.
  • Harmonic Usage Intelligence[8]Groups prompts, files, responses, and supported agent actions into tasks and use cases.
  • Browser Detection and Response (BDR)[2][7][9]Detects, mitigates and threat-hunts client-side web attacks against employees in real time.
  • SquareX Browser Extension (Enterprise Browser)Installs as an extension that turns any browser on any device into an enterprise-grade secure browser.
  • Browser DLP[2]Applies data loss prevention controls inside the browser to secure any browser on any device.
Categories
Headquarters
Not stated on its pagesNot stated on its pages
Founded
Not stated on its pagesNot stated on its pages
Ownership and funding
Privately heldOwned by Zscaler since 2026[3][10]
Named customers
Not stated on its pagesNot stated on its pages
Recent news
Not stated on its pages
  • February 6, 2026Zscaler announced its acquisition of SquareX, a Singapore-based browser detection and response technology startup.[10]
G2 and Gartner Peer Insights
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
Who it fits
Not written yetFrom its own pages, SquareX sells mainly to organizations that want to detect, mitigate and threat-hunt client-side attacks. SquareX describes access for contractors and BYOD users through a containerized browser session. SquareX describes developer environments built from containerized desktops tailored to each developer or team. SquareX access controls work across managed, unmanaged and BYOD devices.
Last verified
November 3, 2026November 2, 2026

Where they overlap

  • Harmonic Security and SquareX are both filed under Data loss prevention.

Where they differ, field by field

  • Harmonic Security's primary category is Workforce AI usage security; SquareX's is Browser protection extensions.
  • Harmonic Security is also filed under AI model and agent security and AI governance.
  • Harmonic Security lists Harmonic Command, MCP Gateway, Harmonic Endpoint Agent and Harmonic Usage Intelligence. SquareX lists Browser Detection and Response (BDR), SquareX Browser Extension (Enterprise Browser) and Browser DLP.
  • Harmonic Security is privately held. SquareX is owned by Zscaler, since 2026.

What it sells: Harmonic Security

What Harmonic Command does[3]
Harmonic Command covers workforce AI use across supported browsers, desktop applications, command-line tools, AI APIs, and agentic workflows that use MCP. Harmonic Command intercepts the action and guides the user or agent toward a safer path.
What MCP Gateway does[2][3][4][6]
Supported OpenTelemetry sources and the local MCP Gateway extend Harmonic coverage to additional native, command-line, and MCP activity. The Harmonic MCP Gateway pairs with the Endpoint Agent and applies to agentic workflows. The MCP Gateway runs on Windows, macOS, and Linux.
What Harmonic Endpoint Agent does[6]
The Harmonic Endpoint Agent detects Claude Desktop, Claude Code, Claude Cowork and OpenAI Codex on macOS and Windows. The Endpoint Agent identifies locally hosted models such as Ollama on employee devices and ties that activity to the process and user behind it. Harmonic identifies connections to inference endpoints like OpenAI, Anthropic, Bedrock and Azure AI Foundry.

Questions about Harmonic Security and SquareX

What do Harmonic Security and SquareX sell?
Harmonic Security sells Harmonic Command, MCP Gateway, Harmonic Endpoint Agent and Harmonic Usage Intelligence. SquareX sells Browser Detection and Response (BDR), SquareX Browser Extension (Enterprise Browser) and Browser DLP.
Are Harmonic Security and SquareX in the same category?
They share Data loss prevention. Harmonic Security's primary category is Workforce AI usage security and SquareX's is Browser protection extensions.
Who owns Harmonic Security and SquareX?
Harmonic Security is privately held. SquareX is owned by Zscaler, since 2026.
Who are Harmonic Security and SquareX sold to?
From its own pages, SquareX sells mainly to organizations that want to detect, mitigate and threat-hunt client-side attacks.
What have Harmonic Security and SquareX announced recently?
February 6, 2026: Zscaler announced its acquisition of SquareX, a Singapore-based browser detection and response technology startup.

About Harmonic Security

Harmonic Security sells AI Governance and Control (AIGC), a control layer that secures and enables the AI-First workforce. Harmonic Security describes a platform that classifies every AI task, discovers why it is used, and controls it in real time. Harmonic Command covers workforce AI use across supported browsers, desktop applications, command-line tools, AI APIs, and agentic workflows that use MCP. Harmonic Command coverage includes ChatGPT, Claude, Copilot, Gemini, Cursor, and more than 1,000 web AI tools.[1][2][3]

Harmonic Command gives security teams visibility into how employees and agents use AI, plus controls for using the tools safely. Supported OpenTelemetry sources and the local MCP Gateway extend Harmonic coverage to additional native, command-line, and MCP activity. The Harmonic MCP Gateway pairs with the Endpoint Agent and applies to agentic workflows. The MCP Gateway runs on Windows, macOS, and Linux.[2][3][4][6]

The Harmonic Endpoint Agent identifies every native AI app, AI-first IDE, CLI tool, locally hosted model and direct inference API call running on employee devices. The Harmonic Endpoint Agent detects Claude Desktop, Claude Code, Claude Cowork and OpenAI Codex on macOS and Windows. Harmonic identifies connections to inference endpoints like OpenAI, Anthropic, Bedrock and Azure AI Foundry, and ties each connection back to the process and user that initiated it. The Endpoint Agent identifies locally hosted models such as Ollama on employee devices and ties that activity to the process and user behind it.[6]

Harmonic secures AI use in the browser with real-time visibility and control over how employees use AI tools. Harmonic identifies the specific account type and subscription plan in use. The Harmonic browser extension finds AI features running inside web apps, such as Magic Write in Canva. Harmonic can warn users as they are about to paste sensitive data, ask for a business justification, or steer them from an unsafe free tool to a sanctioned alternative. The Harmonic browser extension supports Chrome, Edge, Firefox and Safari, plus other Chromium browsers including Arc, Brave, Vivaldi, Island and Genspark.[7]

Harmonic Usage Intelligence groups prompts, files, responses, and supported agent actions into coherent tasks and organization-specific use cases, with views by department, employee, application, approval status, and time. Harmonic builds an inventory of the AI apps a workforce uses, who uses them and for what work. Harmonic records which tools are approved, how policy was applied, what was coached or blocked, and where sensitive data was exposed. Harmonic offers configurable retention, role-based access, employee masking and EU or US hosting. Harmonic does not train on customer data.[5][8][9]

Harmonic uses purpose-built small language models that read the whole prompt or file and interpret the nuance of natural language. Harmonic lets customers enforce enterprise accounts where data is ring-fenced, or restrict uploading corporate context into personal accounts. Harmonic can prevent the upload of protected health information and personally identifiable information to non-compliant models. Harmonic Security says it works with health systems, hospitals, payers and life sciences companies. Harmonic Security says it works with insurance carriers, brokers, MGAs and reinsurers. Harmonic can be deployed through Intune, Jamf, Kandji, or Group Policy.[1][2][3][4][5][8][10][11][12][13]

Harmonic Security on the record

Sources

Harmonic Security full record

  1. [1]Harmonic Security | AI Security for the WorkforceHarmonic Security · undated page, accessed November 3, 2026 · Tier A
  2. [2]Harmonic Security Raises $50 Million Series B Enabling Safe AI Adoption for Millions More EmployeesBusiness Wire · businesswire.com · published October 14, 2026 · Tier A
  3. [3]Harmonic Command: AI Governance & Usage Intelligence Platform | Harmonic SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  4. [4]Harmonic Explore: AI Usage Visibility & Shadow AI Discovery | Harmonic SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  5. [5]Harmonic Guide: Real-Time AI Policy Enforcement & Inline Controls | Harmonic SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  6. [6]Endpoint AI Security & ControlHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  7. [7]Browser-Based GenAI SecurityHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  8. [8]AI Usage IntelligenceHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  9. [9]AI Usage Governance: Enterprise AI Policy & ControlHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  10. [10]DLP for Generative AIHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  11. [11]GenAI Compliance for Regulated IndustriesHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  12. [12]AI Security for HealthcareHarmonic Security · undated page, accessed November 10, 2026 · Tier A
  13. [13]AI Security for InsuranceHarmonic Security · undated page, accessed November 10, 2026 · Tier A

SquareX full record

  1. [1]Squarex discloses architectural limitations of browser devtools in debugging malicious extensions 302518583SquareX via PR Newswire · prnewswire.com · published July 31, 2025 · Tier A
  2. [2]sqrx.comSquareX · sqrx.com · undated page, accessed September 27, 2026 · Tier A
  3. [3]Zscaler acquires squarexZscaler · zscaler.com · published February 5, 2026 · Tier A
  4. [4]Showcasing our Industry-First BDR Solution in Singapore | by SquareX | SquareX LabsSquareX Labs · published October 23, 2024 · Tier A
  5. [5]An Evening of Browser Security: SquareX’s RSAC Networking Dinner | by SquareX | SquareX LabsSquareX Labs · published May 7, 2025 · Tier A
  6. [6]SquareX | Browser Detection and Response (BDR) SolutionSquareX · undated page, accessed October 28, 2026 · Tier A
  7. [7]SquareX: Pioneering Browser Detection and Response (BDR)SquareX · undated page, accessed November 10, 2026 · Tier A
  8. [8]SquareX Receives the Technology Excellence Award by SBR in Cybersecurity, Internet and New Media Category | by SquareX | SquareX LabsSquareX Labs · undated page, accessed November 10, 2026 · Tier A
  9. [9]6 Reasons Why Enterprises Are Shifting from VDI to SquareX | by Engineering @ SquareX | SquareX LabsSquareX Labs · undated page, accessed November 10, 2026 · Tier A
  10. [10]Zscaler extends zero-trust security to browsers with SquareX acquisition | CSO OnlineCSO Online · published February 6, 2026 · Tier B

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