Cookie and Browser Storage Notice
Last updated: 5 November 2026
This notice explains how LEON Sci uses cookies, browser storage and device information on its website and in its account functions.
LEON Sci is operated by Dr. Shahin Ghaziani, Germany. You can contact us at info@leon-sci.com. Our Legal Notice contains further operator details. Our Privacy Notice explains how we process personal data, including service providers, retention and your rights.
Cookies used for your account
Cookies are small pieces of information stored by your browser. We use the following first-party cookies to support registration, account completion, recovery and sign-in.
| Cookie | What it does | How long it lasts |
|---|---|---|
__Host-leon-registration | Keeps track of your registration and email-verification steps. | 15 minutes at a time. Valid registration activity can renew this period. |
__Host-leon-completion | Keeps track of the steps needed to complete your account. | Usually up to 15 minutes; the remaining time can be shorter. |
__Host-leon-recovery | Keeps track of your requested account-recovery process. | Normally up to 15 minutes. Starting a new recovery process can replace it. |
__Host-leon-session | Keeps you signed in to your account. | A browser-session cookie, without a persistent expiry set by LEON Sci. Your browser's session-restoration settings may preserve or restore it. |
Short-lived cookies may remain in your browser until they expire or are replaced, even after a registration or recovery step has finished.
Successful account completion or sign-in sets the sign-in cookie automatically. Closing your browser does not guarantee sign-out because your browser may restore the cookie. Use Sign out when you finish on a shared device.
Separately, account access expires after 30 days without active use or 90 days from fresh sign-in, whichever comes first. Security measures may end access sooner. These access limits are different from the browser cookie's lifetime.
Signing out clears the sign-in cookie. It does not itself delete your account, server records or copies held by service providers. The Privacy Notice explains their separate retention rules.
Display preferences and device information
We use your browser's session storage to remember display choices within a tab. The following entries do not add a unique visitor identifier:
| Storage entry | What it remembers | How long it lasts |
|---|---|---|
leon.shell.navigationOpen | Whether the navigation panel is open or closed. | The tab's browsing session. |
leon.shell.sidebarOpen | Whether an available sidebar is open or closed. | The tab's browsing session. |
leon-how-experience-restart | Your selected sound and motion choices when the “How LEON Sci Works” experience reloads. | Removed when the experience reads it; otherwise the tab's browsing session. |
Reloading a page can preserve these choices. Signing out does not automatically clear them. Browser session restoration can also preserve tab-session storage, so closing a browser window does not guarantee that every preference has been removed.
Some pages read your browser's language, time zone, reduced-motion preference and screen or input settings to adapt their appearance and interaction. Detected language and time zone are used locally for display. When you save account preferences, we process the settings you choose to save. These display functions do not obtain your precise physical location; a professional-profile location you choose is a separate account setting.
Necessary functions and tracking
We use short-lived account cookies and tab-limited display preferences to support functions you request. Where storage or device access is strictly necessary to provide a digital service you expressly request, we rely on section 25(2), no. 2 of the German TDDDG without separate consent. The Privacy Notice explains the separate grounds for processing personal data.
We do not use optional visitor analytics or session replay. Sound and motion controls adjust the experience; they are not consent to unrelated tracking. Accepting our Terms or acknowledging the Privacy Notice does not give consent to unrelated tracking either.
Service providers and external websites
We use Amazon Web Services (AWS) for hosting and account services, including Amazon Cognito for authentication. Frankfurt, Germany is our primary infrastructure location. Provider processing and support may also take place elsewhere; a German hosting location does not mean that all processing stays in Germany or the EEA.
Our Privacy Notice explains the relevant providers, their roles, processing locations, international transfers and retention. The cookies listed above are LEON Sci's first-party cookies; technical providers help us operate the services associated with them.
Following an external link takes you to another website, which has its own privacy and cookie information.
Your choices and privacy requests
Your browser settings let you inspect, block or delete cookies and other website storage. Blocking cookies needed for registration, recovery or sign-in may prevent those functions from working.
Deleting browser storage is different from ending your account or asking us to delete personal data held by LEON Sci and its providers.
For privacy questions or requests, email info@leon-sci.com. You do not need an account or a special form. The Privacy Notice explains your rights and how to make a complaint.