Every organisation now has an AI policy, whether or not it has written one down. If the approved route to a useful tool is slow or missing, staff find their own: a personal chatbot account to tidy up a client email, a browser extension that summarises meetings, a free transcription service, a code assistant on a developer's laptop. None of this is malicious. Most of it is people trying to work faster. But each of those tools is a data flow you did not design, cannot see and may not be able to explain to a customer or the ICO.

That is shadow AI. This article explains how to find it, how to decide which uses matter, and how to bring the useful ones under control without driving the rest further underground.

Why shadow AI is different from ordinary shadow IT

Unsanctioned software has always existed. AI tools raise the stakes in three ways.

Step 1: Discover what is actually in use

Discovery should combine technical evidence with simply asking people. Neither is complete on its own.

Technical sources

Asking people

Run a short, amnesty-style survey: which AI tools do you use, for what tasks, and with what kind of data? Make it clear that the aim is to provide safe tools, not to discipline anyone. You will learn which use cases are valuable, which is exactly what you need to design approved alternatives.

Step 2: Build an AI inventory that is useful, not exhaustive

Record each tool with enough detail to make a decision:

The NCSC's guidelines for secure AI system development put inventory and asset tracking at the start of secure deployment, and the same thinking underpins the UK AI Cyber Security Code of Practice. If you are aiming for ISO/IEC 42001, this inventory becomes the foundation of your AI management system scope.

A simple triage rule

  • Act now: personal or client data going into a consumer-tier tool with no contract.
  • Act soon: any AI tool that can take actions with corporate credentials.
  • Approve or replace: high-value uses with low-risk data, where a business tier or approved alternative exists.

Step 3: Assess the data risk properly

For tools that handle personal data, UK GDPR applies in the ordinary way. You need a lawful basis, transparency, appropriate security and, where processing is likely to be high risk, a data protection impact assessment. The ICO's guidance on AI and data protection is clear that using AI does not change these obligations; it often makes them harder to meet.

The practical questions to answer for each significant use are:

Where the honest answer is "we cannot control what goes in", technical redaction is the usual fix. Stripping identifiers from prompts before they leave your boundary means a tool can still be used for drafting and analysis without the personal data. Our article on tokenisation, encryption and pseudonymisation under UK GDPR explains the options.

Step 4: Govern by offering a better path

Blanket bans are tempting and usually fail. They remove visibility while leaving the demand in place. A more durable approach has four parts.

  1. Provide approved tools for the common tasks identified in your survey, on business terms, with single sign-on so access is tied to employment.
  2. Publish a one-page AI acceptable use statement that tells people what data may and may not go into which tools, how to check AI output before relying on it, and how to request a new tool.
  3. Block or restrict the highest-risk categories technically, for example consumer AI services for users who handle special category data, or unreviewed browser extensions.
  4. Monitor and repeat. Re-run discovery quarterly. New tools and new AI features in existing tools appear constantly.

If your organisation trades with EU customers or deploys AI that affects EU residents, it is worth knowing that the EU AI Act has applied an AI literacy expectation since February 2025; the 2026 Omnibus softened the company duty, but customers still ask how staff are trained. Our EU AI Act guide for UK businesses covers when the Act reaches UK firms.

Where Microsoft 365 Copilot fits

For many organisations the approved alternative is an enterprise assistant such as Microsoft 365 Copilot. That is a sensible route, but it brings its own risk: Copilot makes your existing permissions far more discoverable. Before you present it as the safe option, read our Microsoft 365 Copilot security review checklist.

How Pyralink helps

For the cloud accounts those tools run in, PyraLink™ Prove collects read-only configuration evidence. To talk about shadow AI risk, contact Pyralink.

Frequently asked questions

What is shadow AI?

Shadow AI is the use of AI tools, features or integrations that the organisation has not approved or assessed, such as personal chatbot accounts, AI browser extensions, meeting assistants or AI API keys embedded in code.

Should we ban public AI tools?

Bans tend to reduce visibility rather than use. A more effective approach is to provide approved tools for common tasks, publish a short acceptable use statement, and technically restrict the highest-risk combinations of tool and data.

How do we find out which AI tools staff are using?

Combine DNS, proxy and identity provider logs, browser extension inventories, expense data and code repository scans with a short, no-blame staff survey. Each source catches tools the others miss.

Does UK GDPR apply to prompts sent to AI tools?

Yes. If a prompt contains personal data, sending it to an AI service is processing under UK GDPR. You need a lawful basis, appropriate security and suitable contractual terms with the provider, and may need a DPIA.

PyraLink™ Prove

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Sources: NCSC: Guidelines for secure AI system development; ICO: Guidance on AI and data protection; DSIT: AI Cyber Security Code of Practice; ISO/IEC 42001:2023 Artificial intelligence management system; European Commission: AI Act regulatory framework.