Last updated May 2026
Vellum does not collect, store, transmit, or sell any personal data.
Vellum injects CSS and a canvas animation into claude.ai and chatgpt.com to apply your chosen theme. It does not read, modify, or transmit any conversation content, personal information, or browsing activity.
Your selected theme, Pro status, and license key (if applicable) are saved using Chrome's built-in sync storage. This data stays within your browser and syncs across your devices through your Google account. Vellum has no server and cannot access this data.
Vellum also stores a single flag in your browser on claude.ai and chatgpt.com recording when your free trial began. This exists only so that reinstalling the extension does not restart the trial. It contains no personal information and is never transmitted anywhere.
When you activate a Pro license key, Vellum sends the key to our own validation service (vellum-license.gameitorium35.workers.dev), which forwards it to Polar to confirm it is valid. Vellum re-checks the key periodically so that cancelled or expired subscriptions are reflected. No personal data is included in these requests.
If you enter a company access code, Vellum requests that company's theme configuration from our configuration host (weathered-pond-d21a.gameitorium35.workers.dev). The request contains only the code you entered.
These are the only external network requests the extension makes.
None. No analytics, no telemetry, no cookies, no fingerprinting, no tracking scripts of any kind.
The only external service involved is Polar for payment processing and license validation, governed by their own privacy policy. Vellum does not share data with any other third party.
If this policy changes, the updated version will be published at this URL. Vellum will never introduce data collection without clear notice to users.
Questions can be sent to supportvellumapp@gmail.com.