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Harmonic raises third funding in 14 months from insiders

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Focus on AI's math and reasoning capabilities

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Plans to explore commercial use cases in software

development

By Krystal Hu

Nov 25 (Reuters) - Harmonic, an artificial intelligence

startup co-founded by Robinhood CEO Vlad Tenev, has raised $120

million in new funding, valuing the company at $1.45 billion, as

it tackles AI "hallucinations" - or incorrect or nonsensical

answers - by improving the ability to reason.

The Series C round for the pre-revenue startup was led by

Ribbit Capital, with participation from existing investors

Sequoia and Kleiner Perkins. Laurene Powell Jobs' investment

firm Emerson Collective joined as a new backer.

The deal marks the company's third major fundraising in 14

months, bringing its total capital raised to $295 million,

highlighting strong investor interest in startups trying to make

AI more accurate and reliable, even before they have commercial

products.

Harmonic is developing what it calls "Mathematical

Superintelligence" (MSI), a form of AI focused on advanced

reasoning that it claims is free of hallucinations and other

factual errors that plague many generative AI models.

It says its flagship model, Aristotle, trained on synthetic

math proofs - computer-generated examples used to teach

problem-solving - achieved a top-level performance at the

International Mathematical Olympiad in July alongside Google and

OpenAI, a win that CEO Tudor Achim said helped attract investor

interest.

Founded in 2023, Harmonic says it can achieve this by using

formal reasoning, requiring its AI to output its reasoning as

computer code in the Lean4 programming language, which can be

checked for correctness. The bulk of the new funding will go

toward the immense computing power required for training its

models, according to Achim.

By focusing on verifiable, error-free logic, Harmonic says

it aims to build trust for AI in safety-critical industries like

aerospace and finance, where mistakes can have severe

consequences.

"The elimination of hallucinations comes directly from the

fact that we require our system to output reasoning as code

instead of reasoning as English," CEO Tudor Achim said in an

interview.

Harmonic currently offers its Aristotle model to the public

via a free API, a tool that lets developers plug the model into

their own software. The company said mathematicians and

researchers have been using the tool to check complex proofs and

accelerate novel discoveries. Achim said it will explore

commercialization in the future.

"I think there are certain areas of software development

where safety and reliability are paramount," he said, adding

there is also demand from safety-critical sectors such as

automotive and aerospace.