COMPARISON
Locke vs Prompt Security
Prompt Security is a GenAI security platform covering the full range of LLM risks: preventing sensitive-data leakage to AI tools, defending homegrown LLM apps against prompt injection and jailbreaks, and surfacing shadow AI. It inspects prompts and model responses across many models, offered as SaaS or on-premise, with a browser extension for employees and an API for in-house apps. (Prompt Security was reported to be acquired by SentinelOne; ownership and packaging may continue to evolve — confirm current details with the vendor.) The contrast with Locke is scope and trust model: Prompt Security is a broad suite that inspects content through its platform; Locke is a focused, local-first, zero-knowledge control for sensitive data in prompts. (Category-level as of 2026 — verify specifics with the vendor.)
When Prompt Security fits
- You need broad GenAI security: prompt-injection and jailbreak defence for homegrown LLM apps, plus employee-facing controls.
- You want one platform covering shadow-AI discovery, response inspection, and policy across many models.
- Your security team prefers a managed platform (SaaS or on-premise) with centralised GenAI policy enforcement.
When Locke fits
- Your priority is sensitive data in prompts, detected and masked on the device before anything is sent.
- Zero-knowledge is a hard requirement — no platform should inspect the content you are protecting.
- You want a free starting point (Canary) and a per-user desktop app (Locke, coming soon) rather than a full GenAI-security suite.
Side-by-side
| Dimension | Locke | Prompt Security |
|---|---|---|
| Scope | Sensitive data in AI prompts, masked on the device. | Broad GenAI security: leakage, injection, jailbreaks, shadow AI. |
| Where inspection runs | On the device, before any network call. | Through the platform (SaaS or on-premise), inspecting content. |
| Trust model | Zero-knowledge: the vendor never sees prompt content. | Content is inspected by the platform to enforce policy. |
| Entry point | Free OSS Canary now; Locke desktop app coming soon. | Commercial platform — contact vendor for current pricing. |
| Best for | Local-first, zero-knowledge control of AI prompts. | End-to-end GenAI security across apps and employee use. |
Bottom line
Prompt Security is a broad GenAI-security platform — useful if you also need injection defence for your own LLM apps and centralised policy across employee AI use. Locke is narrower and local by design: it keeps sensitive prompt data on the device, with nothing for a vendor to inspect. Need full GenAI-security coverage? Look at Prompt Security. Need local-first and zero-knowledge above all? That's Locke. Confirm current capabilities and ownership with the vendor.
