Privacy Policy

Last updated September 22, 2026.

Your textbooks and study notes stay on your Mac. This policy explains the separate information used to run the website, support you, process purchases, and verify licenses.

marginstudy is developed and operated by Alric Siu (“marginstudy,” “we,” or “us”). For privacy questions or requests, email info@marginstudy.app.

Inside the app

marginstudy stores notes, scratchpads, bookmarks, and reading positions locally on your Mac. It references PDFs at their original locations. Reading and writing features do not require a marginstudy account or send your textbook content to a marginstudy server.

We do not have access to your locally stored notes or keep a server backup of your workspace. If files on your Mac are deleted or corrupted, we cannot restore your notes from our systems. Recovery depends on a usable backup or local recovery copy that you control. Keep your own backups of your PDFs and marginstudy workspace.

You control your workspace files and exported backups. If you put them in a folder synchronized by another service, that service’s settings and privacy policy apply. We cannot retrieve or delete local files on your behalf. We only receive note content if you choose to send it to us, for example in a support email.

Trial and license activation

The direct-download app includes a 14-day trial. marginstudy stores the trial start and license securely in your Mac’s Keychain. The current direct-download version uses Lemon Squeezy for license activation, validation, and deactivation.

For those checks, the app sends your license key and a randomly generated installation label or license-instance identifier. Lemon Squeezy can associate them with your purchase and processes connection information such as your IP address. Your textbooks, notes, and scratchpad content are not sent for licensing.

marginstudy checks activated licenses periodically and supports up to 30 days of offline use after a successful check. You can deactivate this Mac from the app’s License & Trial menu. See Lemon Squeezy’s privacy policy for its processing practices.

Basic app analytics

We use PostHog to understand and improve marginstudy during the trial and after activation. We collect when the app is opened, when a license is activated, trial-popup appearances and button choices, trial or license status, the app version, and the number of different books opened.

A random identifier lets us recognize repeat visits from the same installation without linking this activity to your name, email, or purchase details.

We do not send your license key, book titles or contents, notes, or scratchpad content. We do not record your screen or what you read or write. PostHog receives connection information such as your IP address when processing requests. See PostHog’s privacy policy.

Website hosting

Cloudflare hosts this website and processes connection information, including IP addresses and request metadata, to deliver and secure it. See Cloudflare’s privacy policy.

Purchases

Lemon Squeezy is the merchant of record for purchases through this website. It processes information needed to complete your order, such as your name, email address, billing address, payment details, and transaction information. Payment card entry happens through Lemon Squeezy’s checkout; we do not receive your full card number. See Lemon Squeezy’s privacy policy for its handling of purchase information.

We receive or can access order information needed to deliver and support your purchase, such as your purchase email, order reference, product, payment status, and license details. We use it to provide access, handle support and refunds, and maintain required business records.

Support

If you email us, we receive your email address, message, and any attachments you choose to send. We use them to respond, troubleshoot, and handle your request.

Please send only information relevant to your request. You do not need to share private PDFs, note content, full payment card details, or your full license key. Our email service processes messages to deliver and store correspondence.

Why we use information and who receives it

We use purchase and license information to provide the app you request, support messages to respond to you, and website analytics and trial-popup activity to operate, secure, and understand the site and trial experience. Where data protection law requires a legal basis, these purposes rely on performing our agreement with you, our legitimate interests in providing and securing the service, or meeting legal obligations, as applicable.

We use the service providers described above for hosting, payment, licensing, analytics, and email. We may also disclose information where required by law or necessary to address fraud, protect legal rights, or secure our services. We do not sell personal information or share it for cross-context behavioral advertising.

Retention and international processing

Local study files remain under your control. We retain support correspondence and purchase records for as long as needed to handle your request, support your license, resolve disputes, and meet applicable accounting or legal obligations. The reason for keeping the record determines its retention period.

Service providers may process information outside your country, including in the United States. Their linked privacy notices explain their locations, retention practices, and safeguards for international transfers.

Your choices and rights

You can manage or delete your local workspace files and backups yourself. You can also contact info@marginstudy.app to request access to, correction of, or deletion of personal information we hold about you.

Depending on where you live, you may also have rights to restrict or object to processing, obtain a portable copy, or complain to a data protection authority. We may need to verify your request and retain records where the law requires it. Requests about information held independently by your payment provider can also be sent directly to that provider.

Changes to this policy

We will update this page when our practices change and show the latest date above. We will provide additional notice or obtain consent when required by applicable law.