Proton Introduces Lumo: A Privacy-First AI Chatbot

Key Takeaways:

Proton has launched Lumo, an AI chatbot built to protect user data via local encryption and zero-access policies.
The chatbot handles document summaries, code generation, email writing, and more, while keeping data private and encrypted on-device.
Lumo supports web searches through privacy-focused engines, file analysis, and integration with Proton Drive, all with user-controlled privacy.
Powered by open-source models (Mistral Nemo, Nvidia OpenHands, OLMO 2), it offers tiered access including a $12.99/month Lumo Plus plan.
Positioned as a privacy-centric alternative to mainstream AI like ChatGPT, Gemini, and Copilot, Lumo emphasizes user data control and transparency.

Proton, the company known for end-to-end encrypted services like Mail, VPN, and Drive, has launched Lumo, an AI chatbot that makes privacy its cornerstone. Unlike other generative AI tools, Lumo ensures users’ inputs and chat history remain local and inaccessible to Proton or third parties.

We believe the benefits of AI are too great to miss, and the risks too serious to ignore. Whether we like it or not, AI is here to stay, but the current iterations of AI reflect a failure to learn from the past. That’s why we built Lumo — a private AI assistant that only works for you, not the other way around. With no logs kept and every chat encrypted, Lumo keeps your conversations confidential and your data fully under your control — never shared, sold, or stolen.
Eamonn Maguire

Privacy by Design

Lumo is built on a zero-access encryption model—users hold the decryption keys for their data, which means even Proton cannot read messages, uploads, or outputs. Storage and processing happen under user control, keeping sensitive content private while allowing convenient interaction.

Productivity Meets Security

Despite its privacy-first architecture, Lumo doesn’t skimp on capability. The assistant can summarize documents, generate code, help compose emails, and more. It can also access encrypted files stored on Proton Drive, enabling secure document analysis without compromising privacy.

Additionally, Lumo offers a privacy-mode web search—recommended for users needing external information without compromising data integrity. By default, search is disabled to ensure maximum privacy.

Open-Source Power Under the Hood

Lumo doesn’t rely on proprietary models. Instead, it uses several open-source LLMs, including Mistral’s Nemo and Small models, Nvidia OpenHands 32B, and AI2’s OLMO 2 32B. Proton dynamically selects the best-performing model for each task, such as using OpenHands for coding-related queries, ensuring efficiency and adaptability without sacrificing privacy.

Access Tiers

Non-registered users: Limited access, no chat history.
Free account holders: Encrypted chat history, small file uploads, and favorites.
Lumo Plus ($12.99/mo): Unlimited chats, extended encrypted history, large file uploads and prioritization.

This tiered approach lets users test the service before committing, with advanced tools available for power users.

A User-Controlled Alternative

Proton positions Lumo as a counterpoint to major AI platforms like OpenAI’s ChatGPT, Google Gemini, and Microsoft Copilot, which often use user data for AI training or advertising. Proton founder Andy Yen emphasized that Lumo is about “AI that puts people ahead of profits,” reinforcing the company’s values around data privacy.

By integrating open-source models with local encryption and flexible deployment, Lumo lets users leverage AI while retaining control over how and where their data is stored and processed.

Why It Matters

As AI assistants become more embedded in work and daily life, privacy concerns are mounting. The Verge notes many mainstream tools collect user data for model improvements. Lumo’s architecture directly addresses these concerns, offering a mainstream-ready alternative for users who want both capability and confidentiality.

Enterprises and privacy-conscious consumers now have an AI assistant that works within their encrypted ecosystem, allowing workflows involving documents, code, and messaging without sacrificing security. For users wary of Big Tech, Lumo offers a trusted alternative.

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Rich Tehrani serves as CEO of TMC and chairman of ITEXPO #TECHSUPERSHOW Feb 10-12, 2026 and is CEO of RT Advisors and is a Registered Representative (investment banker) with and offering securities through Four Points Capital Partners LLC (Four Points) (Member FINRA/SIPC). He handles capital/debt raises as well as M&A. RT Advisors is not owned by Four Points.

The above is not an endorsement or recommendation to buy/sell any security or sector mentioned. No companies mentioned above are current or past clients of RT Advisors.

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Portions of this article may have been developed with the assistance of artificial intelligence, which may have contributed to ideation, content generation, factual review, or editing.