What you can and cannot share with AI

A support agent wants a neater version of a complaint and pastes the whole email thread into ChatGPT. At the bottom are a name, an account number, a phone number and an IBAN. The question was useful. The problem is the context that came with it.

That is how an AI data leak usually starts: not with a hack, but with a paste. A short checklist and a rule of thumb prevent most of it.

#Why this matters: a prompt counts as processing

To you, an AI chatbot feels like a scratchpad with superpowers. Under the GDPR it is something else: a place where data is processed, possibly stored, remembered, analysed or passed to a connected app. Whatever you type, you hand over to the provider. In a personal or free account, that text may also be used to improve the model, unless you have turned that off.

So the first question is not whether the answer is correct, but which data you put in the prompt and whether it needed to be there.

#What you never put in an AI prompt

This data does not belong in a chatbot, not even "just this once":

• Passwords, PINs and recovery codes. Never share login details with anyone.
• National ID, passport or licence numbers. Unique numbers that make a person directly identifiable.
• Bank and credit card details. IBAN, card numbers, CVC.
• Medical information. Lab results, diagnoses, treatment notes. A chatbot is not bound by the same rules as your doctor.
• Customer and patient records. Names combined with files, contracts or payment data.
• Confidential company data. Internal memos, strategy, non-public figures.
• Source code with secrets. API tokens, keys, configuration with credentials.

The common thread: the more a piece of data makes someone identifiable, or the more confidential it is, the stronger your reason to share it has to be. In practice, that reason almost never exists.

#What is usually fine

AI is most useful when you give it the task without the sensitive content:

• General questions. Explanation, structure, brainstorming, language and tone.
• Anonymised text. Replace real names with "Customer A", round amounts, drop locations.
• Dummy data and placeholders. Use name@example.com and Account 0000 instead of the real value.
• Your own non-confidential work. A blog post, a public text, a draft without personal data.

You often do not need the real data to get the task done. You can improve a sentence in a performance review without the salary or medical context. You can draft a payment email with a placeholder IBAN. Keep the task, leave out the identifying details. More techniques are in the prompt redaction guide.

#Watch files and screenshots

Files are the biggest blind spot. A PDF can contain customer names, order numbers, contract parties or retention periods. A phone screenshot can quietly show notifications, email addresses, calendar entries or location data. What you do not see still gets uploaded. So check a file before you put it in an AI tool, or strip out the sensitive parts first.

For a document, that check does not have to rely on your own eyes. Open it in BeeSensible and the sensitive data is highlighted, so you can export a redacted copy instead of the original. It works for screenshots too: the image is read using text recognition. Faces and signatures are not detected; you draw a box over those yourself. If your contracts or client files follow the same layout, PDF after PDF, you can handle them the same way every time.