Last updated 7 November 2026

Privacy notice

This notice explains what Muster does with information. GPT Shop Ltd (company no. 15766335) is the controller. Contact: hello@gptshopltd.com.

Your client list

The company numbers you enter stay in your browser. They're sent to our server only while a check runs, so we can look each company up on the Companies House register. We don't save them. Your browser keeps a copy so you can reopen a report and see what has changed, along with the practice name and sign off you type for client letters. You can clear all of it by clearing this site's data.

Register data

The report contains names and verification dates of company officers and persons with significant control. This is public information published by Companies House, which we read through its API under the Open Government Licence.

Payments

Stripe processes payments as an independent controller and collects your email address and card details. We receive your email, the amount and a fingerprint of the list you paid for, which lets the paid check run only on that list. Stripe's privacy policy is at stripe.com/privacy.

Hosting and logs

The site is hosted by Vercel. Like most hosts it records technical request logs, such as IP addresses, for security and to limit misuse of the free check. We don't use analytics or advertising cookies.

How long we keep things

We keep payment records for six years for tax and accounting. We don't keep client lists or reports.

Your rights

You can ask for access to, correction of or deletion of personal data we hold about you by emailing hello@gptshopltd.com. You can also complain to the Information Commissioner's Office at ico.org.uk.