Proton Lumo and AI Paper Trail: What Does Your AI Actually Know About You?

Most mainstream chatbots store the prompts you type on their servers. Depending on the platform and its default settings, those conversations may be retained for long periods, reviewed, used to train models, or shared with third parties. Proton, the Swiss company behind Proton Mail and Proton VPN, has built two products around that issue: Lumo, an ai assistant designed around encryption and a no logs policy, and AI Paper Trail, a free tool that analyzes your exported chatbot data and reports what it reveals about you.

Here is what both do, how they work, and where they fit among the AI chatbots we cover.

What is Proton Lumo?

Lumo is Proton's AI chat assistant, launched in July 2025. Functionally it covers the same ground as most entries in our AI assistant tools category: answering questions, summarizing and analyzing documents, reviewing code, planning tasks, searching the web in real time, and generating images, a feature more commonly found in a dedicated AI image generator.

Where it differs is in how it handles data. According to Proton:

• Zero access encryption: Conversation history is encrypted so that only the user can read it. Proton states it cannot access chats itself.
• No logs: Lumo does not keep records of conversations on its servers.
• No training on user data: Prompts are not used to train Proton's AI models.
• Open source code: Lumo's code is publicly available, so its privacy claims can be checked rather than taken on trust.
• Swiss and EU legal framework: Proton operates from Switzerland and complies with the EU's GDPR, which governs how user data can be collected and processed.

Lumo received a special mention in TIME's Best Inventions of 2025, which described it as a zero access encrypted chatbot that does not track or record conversations. TechRadar's review notes that the recognition was for the privacy architecture rather than raw AI performance, and points to users who handle confidential information, such as lawyers, journalists, and healthcare workers, as the most obvious audience.

Lumo has a free tier, including guest access without an account, and a paid Lumo Plus tier with higher usage limits, longer chat history, more image generations, and unlimited Projects. Proton also offers Lumo for Business, which applies the same data handling model to team accounts.

What is the AI Paper Trail?

AI Paper Trail is a free tool from the Lumo team. It analyzes the conversation data you export from ChatGPT or Claude and produces a private report showing what that history reveals about you. The reasoning behind it: individual prompts may seem harmless, but months of accumulated chats about work, health, finances, and plans can add up to a detailed personal profile.

According to Proton, the report includes:

• My Privacy Type: a label based on how you approach data privacy
• My AI Exposure Score: a score based on the number of data points extracted from your chats and how much they reveal
• What AI knows about me: the personal details your conversations expose, such as habits, relationships, occupation, and location
• My data value: an estimate, in dollar terms, of what your data is worth to your AI provider

Users can also generate a shareable report card that summarizes the findings without exposing the underlying personal details.

How it works

1. Export your conversation data from your AI platform. AI Paper Trail currently supports ChatGPT and Claude exports, with more platforms planned, per Proton.
2. Go to AI Paper Trail.
3. Upload the exported file and review your report.

Proton states that uploaded data is deleted as soon as it is analyzed, is never stored on Lumo's servers, and that the report is visible only to the user.

The context

Data handling has become a live issue across the AI industry. As we reported recently, OpenAI has moved to strengthen its own privacy protections, a sign that vendors are responding to growing user concern about where prompts end up. Proton's position is that most major platforms retain more than users realize by default, including conversations, uploaded files, usage patterns, device and network data, and account information.

AI Paper Trail is a way to test that claim against your own history rather than anyone's marketing. Heavy chatbot users, for example anyone who has been using ChatGPT daily since reading a guide like our how to use ChatGPT walkthrough, will have the most material to analyze. The tool also fits a wider trend we track across AI private search engine tools and adjacent categories, where privacy is increasingly treated as a product feature rather than a footnote.

Conclusion

Lumo is not positioned as the most capable model on the market, and reviewers have not claimed it is. Its case rests on verifiable data handling: encryption, no logs, open source code, and Swiss jurisdiction. Whether that trade suits you depends on how sensitive your prompts are and how much weight you place on being able to audit the claims.

AI Paper Trail is useful regardless of whether you intend to switch assistants. It costs nothing, works with exports you can already download from ChatGPT or Claude, and answers a question most users have never been able to check for themselves: what does my AI know about me?