Privacy Policy

Last updated: October 2026

This Privacy Policy applies to the public landing site at bayesimpact.org, operated by Bayes Impact France (Association de loi 1901, SIREN 813 821 279, 146 rue de Rivoli, 75001 Paris) and its US affiliate Bayes Impact (501(c)(3), EIN 47-1102475).

For privacy practices governing the Bayes Platform application (platform.bayesimpact.org), please refer to the dedicated platform privacy policy.

1. What we collect on this site

This site is a static publication hosted on Vercel. Its pages run no server-side code and we maintain no database; the only server-side processing is two small functions that relay the form submissions described in section 2. We do not set tracking or advertising cookies. We measure the site's audience with PostHog, in a cookieless mode described in section 3.

The only data processed comes from:

  • Browser server logs — When you visit any page, Vercel (our host) may transiently log standard request metadata (IP address, user agent, request timestamps, requested URL) for security and operational purposes. This is governed by Vercel's Privacy Policy.
  • Forms you voluntarily submit — The contact form, the newsletter signup, and the Impulse.Healthcare signup form transmit the data you enter (name, email, organization, message) to us or our designated processors (see section 2).
  • Audience measurement — The pages you view and the links you click are sent to PostHog (see section 3).
  • Local browser storage — This site does not use cookies or localStorage for tracking. Your language preference is determined by the URL you visit (e.g. /fr/about).

2. How your form data is processed

The data you voluntarily enter into our forms (name, email, organization, message) is processed as follows:

  • Contact form — Submissions are routed directly to our internal email so we can respond to your inquiry, and are kept only as long as necessary to process your request.
  • Newsletter & Impulse.Healthcare signups — These signups (email address, plus an optional organisation you may share so we can tailor content to your sector) are processed and managed by our designated processor Mailchimp (The Rocket Science Group LLC, USA — see the Intuit Mailchimp Privacy Statement). The transfer to the United States is covered by the EU-US Data Privacy Framework, to which Intuit is certified.

3. Tracking pixels & analytics

Our emails sent via Mailchimp contain an invisible tracking pixel (a 1x1 image). When you open an email or click a link, this technology transmits technical data to us (time of opening, IP address, device type). This data helps us analyze the performance of our campaigns and tailor our future content to your interests.

This measurement only happens if you agreed to it. It rests on a consent that is separate from the subscription itself, asked for by its own tick box when you give us your address, and left unticked by default. Declining changes nothing about your subscription: you receive the newsletter either way, without your opens and clicks being measured. If you subscribed through the contact form, no such consent was requested, so no measurement is applied. You can withdraw it at any time by writing to our data protection contact below, and you can block the pixel yourself by turning off the automatic loading of remote images in your email client.

Website audience. We use PostHog (PostHog Inc., data hosted in the European Union) to count visits and see which pages and links are used. The measurement is cookieless: it writes nothing on your device, keeps a random identifier only while the page is open, and records no session replay. We cannot recognise you from one visit to the next, and we never link this data to your identity. You can block it with any content blocker.

4. Why we process this data

To respond to your contact request, send you our newsletter if you subscribed, or keep you informed of program updates (Impulse.Healthcare). We do not sell or share your data with third parties for marketing purposes. Server logs are retained for security only.

5. Legal basis (GDPR)

Form submissions are processed based on your consent, given by submitting the form. Measuring opens and clicks in our emails rests on a second, separate consent, given by ticking its own box, which you may refuse without affecting your subscription. Server logs and audience measurement are processed based on our legitimate interest in operating a secure website and understanding how it is used (Article 6.1.f GDPR).

6. Retention

Contact requests: kept for the duration needed to respond, then archived for up to 3 years. Newsletter subscriptions: until you unsubscribe (every email contains an unsubscribe link). Impulse.Healthcare signups: until the program ends or you opt out. Vercel server logs: per Vercel's retention policy. Audience data: per PostHog's retention settings for our project.

7. Your rights & consent

The processing of your form data is based on your consent, which you can withdraw at any time. You can opt out of our mailing lists or object to email tracking by clicking the unsubscribe link at the bottom of any email. Alternatively, you can block the tracking pixel by disabling the automatic loading of external images in your email client's settings.

Under GDPR, you also have the right to access, rectify, delete, restrict, or oppose the processing of your personal data, as well as the right to data portability. Contact us at . You may also lodge a complaint with the French data protection authority, the CNIL.

8. Changes to this policy

We may update this policy as the site evolves. Any change will be reflected on this page with the updated date above.