Mirendil, a San Francisco company that builds tools for artificial intelligence (AI) research and development, said on 12 November 2026 that it has raised a $1 billion Series A round led by Kleiner Perkins and Clearlake Capital, according to its press release, distributed by PR Newswire. Crunchbase News, in its weekly list published on 13 November 2026, ranks the round first among the week’s ten largest announced funding rounds for US companies.

The round

  • Other investors named in the release: Battery Ventures, Doerr Capital, Gil & Co, Google, M13, Pear VC and S32, plus other new and existing investors the release does not name.
  • Valuation: the release does not state one.
  • Use of funds: the release does not itemize spending. It says the round will let Mirendil go further toward making AI research and development more accessible, and it describes the company as a small team.

What Mirendil says it has built

The release says that over the past three weeks the company shared its first results. It says one researcher, working with agents, pretrained a competitive coding model called Mirendil-Base from scratch in 3.5 months with less than $10 million in compute. The company says it then post-trained that model into Fern, which holds up to 10 million tokens of context, which Mirendil describes as enough for days of an agent’s work. It says Lor, a system now in private beta, has hundreds of agents write code and run experiments for days at a time, and that Mirendil itself runs on Lor every day.

SiliconANGLE, which reported the round on 13 November 2026, says Mirendil was launched last year by two former Google DeepMind and Anthropic researchers. It names Behnam Neyshabur as chief executive officer and Harsh Mehta as chief technology officer. Anthropic is the maker of Claude. SiliconANGLE also reports that the company’s agents wrote more than 99% of the code behind Mirendil-Base.

Earlier funding and the reported $5 billion figure

SiliconANGLE reported on 25 June 2026 that Mirendil had raised $200 million at a $1 billion valuation in a seed round led by Andreessen Horowitz, with Kleiner Perkins and Nvidia among the contributors. Dealroom News reported on 23 September 2026, citing Bloomberg and people familiar with the discussions, that Mirendil was in talks to raise up to $1 billion at a $5 billion valuation, with Kleiner Perkins in talks to lead. That would be five times the seed valuation (Lens arithmetic).

The $5 billion figure comes from a report of talks. It is not in Mirendil’s release, and Lens has not found it confirmed for the round that was announced. The release also does not name Andreessen Horowitz or Nvidia, the seed investors named by SiliconANGLE, among the Series A participants.

Where reports differ

Mirendil’s release says Mirendil-Base was built with less than $10 million in compute. SiliconANGLE writes that the project cost $10 million. Crunchbase News describes Mirendil as a developer of agentic AI technology for research and development, while SiliconANGLE describes it as a provider of software that speeds up AI development.

Sources and notes

Sources: Mirendil, “Mirendil Raises $1B to Democratize Frontier AI R&D” (PR Newswire, 12 November 2026); the same release on Mirendil’s website; Crunchbase News, “The Week’s 10 Biggest Funding Rounds” (13 November 2026); SiliconANGLE, 13 November and 25 June; Dealroom News, 23 September. PR Newswire’s own page returned an empty response to Lens’ direct request, so Lens read the release in full on Mirendil’s website and in a PR Newswire copy on Morningstar, which matched. Lens read the SiliconANGLE and Dealroom articles as text and read the Mirendil entry and introduction of the Crunchbase News list. Lens did not open the Bloomberg report that Dealroom cites. The model results are Mirendil’s own claims and have not been independently replicated.

Image: Market Street in San Francisco between the Humboldt Bank Building and the Phelan Building, seen from One Kearny Street, 16 February 2017. Photo: Dllu (CC BY-SA 4.0), via Wikimedia Commons; cropped. Stand-in image: not a photo of Mirendil or its offices.