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Daniel De Freitas

Co-founder of Character.AI; led the development of the Meena and LaMDA dialog models at Google

Daniel De Freitas co-founded Character.AI with Noam Shazeer; the company's December 2022 launch post, signed by both, says De Freitas invented and led the development of the Meena and LaMDA dialog systems. De Freitas is a co-author of LaMDA: Language Models for Dialog Applications (2022), which presents Transformer-based language models specialized for dialog, with up to 137B parameters, and reports that fine-tuning with annotated data and letting the model consult external knowledge sources improve safety and factual grounding; a footnote on De Freitas's name says the work was done while at Google.12

At a glance

Current role
None confirmed in the sources
Work listed
2
Sources cited
2
Profile reviewed

Research

Character.AI's launch post credits Daniel De Freitas with inventing and leading the development of the Meena and LaMDA dialog systems at Google. De Freitas is the second-listed author of the January 2022 paper LaMDA: Language Models for Dialog Applications, which describes a family of Transformer-based dialog models pre-trained on public dialog data and web text.12

The LaMDA paper reports that scaling the model alone did less for safety and factual grounding than for quality, and that fine-tuning with annotated data and letting the model consult external knowledge sources improved both. It measures safety against an illustrative set of human values and uses a LaMDA classifier to filter candidate responses.2

Character.AI

De Freitas co-founded Character.AI with Noam Shazeer. The December 2022 post introducing the company, signed by both co-founders and the Character team, describes a product for creating and chatting with AI characters and says the beta had launched that September.1

Work and contributions

  • Meena and LaMDA Published research

    Character.AI's launch post says De Freitas invented and led the development of Meena and LaMDA; De Freitas is a co-author of the 2022 LaMDA paper, with a footnote saying the work was done while at Google.12

  • Character.AI Proprietary product

    Co-founded Character.AI with Noam Shazeer; the December 2022 launch post introducing the company's product is signed by Shazeer, De Freitas and the Character team.1

Timeline

  1. Co-authored LaMDA, Language Models for Dialog Applications, as the second-listed author.2
  2. Character.AI launched its beta, according to the company's launch post.1
  3. Co-signed the post introducing Character.AI with co-founder Noam Shazeer.1

Documented roles

The sources do not confirm a current role; these are the roles they document.

  • Co-founder (December 2022 launch post), Character.AI1
  • Co-author of the LaMDA paper (work done while at Google, per the paper's footnote), Google21

Companies in their history

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References

2 sources · profile reviewed Oct 21, 2026 · data updated Oct 21, 2026

  1. Character.AI blog — Introducing Character (launch post)Character.AI · Announcement · published Dec 5, 2022 · accessed Oct 21, 2026
  2. LaMDA: Language Models for Dialog Applications (arXiv 2201.08239), author list and Google footnotearXiv · Paper · published Jan 20, 2022 · accessed Oct 21, 2026