Dressed head-to-toe in black with gelled-back hair and thick, tinted glasses, H Company cofounder Charles Kantor maintains a consistent style for his, admittedly rare, public appearances.
In the twelve months since H raised a mammoth $220m in seed funding, 26-year-old Kantor has been spotted just a handful of times, sporting his signature style on tech conference panels to discuss his company’s meteoric rise.
The lowkey cofounder’s social media pages have remained dormant and, until last month, he staunchly avoided interviews with the media, only breaking cover when H announced its first batch of publicly-available products.
But despite orchestrating one of the biggest raises ever for a French startup, winning investment from big-name investors like Accel and Bpifrance and earning praise from president Emmanuel Macron — Kantor is now out.
On June 13, amid the fanfare of leading French industry summit VivaTech, H announced Kantor was leaving the company, to be replaced by former Palantir executive Gautier Cloix. Within weeks of Kantor’s surprise exit, the company’s COO Mike Benchimol announced he was also leaving, citing an “intense and hectic year”.
Their departures come less than a year after three of the company’s five cofounders also quit the startup, citing “operational differences”, without revealing further details.
Since then, sources have revealed how Kantor split with the board over plans to build AI infrastructure for the company, which involved raising funds in the billion-euro range. One source familiar with the matter says the project had already secured funding offers.
Another source with knowledge says the board would have found the project came at the wrong time given the significant leadership issues the company had been facing. Wary of Kantor’s pitch for the company’s future, H’s board balked.
“The reasons that pushed Charles Kantor to leave belong to him, but in any case the board and leadership team had been in discussions with Gautier Cloix for months, in order to bring a strategic perspective to secure large customers and enable the company to accelerate its growth,” a spokesperson for H told Sifted.
A Holistic approach
Much of the buzz surrounding H came down to the fact Kantor managed to convince four seasoned DeepMind scientists — Laurent Sifre, Karl Tuyls, Julien Perolat and Daan Wierstra — to work with him on a new company, originally named Holistic AI.
Sifre in particular had previously contributed to DeepMind’s computer program AlphaGo and managed Arthur Mensch, the cofounder of buzzy generative AI company Mistral, himself a DeepMind alum.
From the start, Kantor had big ambitions for H.
“It’s very rare to have someone who at 25 years old tells you: ‘I am not interested in a $3m seed round, I can’t do anything with that’,” says Michaël Obadia, a Paris-based tech headhunter who says he helped Kantor at the beginning of the project in 2023.
“[Kantor] thought: ‘I want to be very ambitious and have a top-level team, otherwise it isn’t worth trying.’ […] Very early, he was thinking big.”
Kantor’s determination was “exceptional”, says Obadia — and had come from a young age, he adds, pointing to the fact he spent his teenage years playing tennis at a semi-professional level.
Through hours of cold calls Kantor eventually connected to Tuyls, Perolat, Wierstra and Sifre in the summer of 2023 while they were still working at DeepMind. Sifted understands Sifre joined the project a few months later, towards the end of 2023.
In early 2024 reports emerged that Tuyls and Sifre were talking to investors.
Asked about the “wild levels of FOMO” among investors keen to get in on the round, one backer tells Sifted: “Because the team was insane […] everybody was over-excited to be a part of it.”
Just months after Mistral had raised a blockbuster €105m seed round, Sifre’s previous links to Mensch, in particular, were a cause for enthusiasm.
“Everybody thought it was going to be the next Mistral,” says one investor. “Unfortunately the team unexpectedly disintegrated a little bit quickly.”
Another person with direct knowledge of the matter says: “The money was raised thanks to the team’s reputation.”
One investor — who does not hold a stake in H — suggested Kantor’s team and the hype generated around French AI by Mistral helped convince investors to get on board, despite his relative lack of experience.
“Accel absolutely needed to do its own Mistral, and H came along just at that moment with DeepMind employees,” they say. Accel did not reply to a request for comment.
From Paris to Stanford
Not much is known publicly about Kantor’s academic or professional experience prior to founding H.
According to his LinkedIn profile, Kantor completed a masters in science and executive engineering at prestigious French engineering school CentraleSupélec from 2019 to 2021. During that time he spent six months as a research fellow at Harvard University; he also founded Klass, a startup leveraging AI tools for the surveillance and analysis of insect populations.
With Klass, Kantor co-wrote a number of research papers and won student-focused awards, including securing in 2020 the first prize for student projects given out by the French branch of global organisation the Institute of Electrical and Electronics Engineers (IEEE).
A source close to Kantor at the time tells Sifted: “Charles was always entrepreneurial […]. As a researcher, he was dynamic, efficient, goal-oriented and a good strategist.”
“He’s a good salesman, a visionary, he’s very well-connected, he knows how to recruit, how to convince, and how to push. I’m not surprised he founded H. I always knew he would create a big startup very quickly.”
In 2021, Kantor was admitted to Stanford University, where he enrolled in a masters degree in computational and mathematical engineering.
During that time he was selected as one of 12 students to join Stanford’s Threshold Venture Fellows (TVF) programme — an initiative focusing on entrepreneurship and intended to familiarise participants with the challenges of launching high-growth companies thanks to weekly sessions and discussions.
Sifted understands however that after the programme Kantor dropped out of Stanford and returned to France at the end of 2022.
Surprise exits
Kantor’s LinkedIn profile states he started H in September 2023, a few months after he returned from the US. While his cofounders rapidly took the spotlight, he firmly assumed the role of CEO of the company, liaising with investors, managing early recruitments and determining the company’s strategy.
Company creation documents show Kantor’s initial stake in the company was 27.8% — as much as Tuyls and Sifre. Wierstra owned 14.4% of shares; Sifted understands Perolat held a founding member role.
“From the start, my interactions with the company have always gone through both Laurent Sifre and Charles Kantor,” one investor in H, who spoke to Sifted on the condition of anonymity, says.
“Yes, [Kantor] was younger and yes, he wasn’t the most experienced […] but it was quite clear from the start he was the boss on the business side.”
But Kantor’s reluctance to share information did not always go down well. “He likes to be mysterious,” one source close to Kantor says. “Some investors didn’t join the round because they didn’t like it. […] But he does it more because he likes it than for strategy.”
Whatever his motivation, Kantor’s approach worked.
In May 2024, the company announced it had raised a dizzying $220m seed round, one of the biggest in France’s history, confidently promising it would solve the puzzle of “AGI” (artificial general intelligence), a long-teased and potentially transformational leap in AI capabilities.
But within months three cofounders — Tuyls, Perolat and Wierstra — had left and the company largely remained in stealth mode, sharing little information even with most of its investors.
Soon questions emerged about H’s development and roadmap, with concerns the startup lacked leadership and vision — just as a growing number of tech companies started to build their own AI agents, including OpenAI and Google.
In the second half of 2024, H quietly acquired Mithril Security, a Paris-based startup developing open-source tools to build AI agents. The company eventually released a series of AI agents earlier this month, including its first publicly-available and commercial products, which it said were better-performing and cheaper than competitors’.
“If we manage to remain state-of-the-art technologically […] we have a chance in this competition,” Kantor told Sifted in an interview at the time.
But a week later, H Company announced Kantor was being replaced by former Palantir exec Gautier Cloix, signalling a split with the board (although Kantor remains a shareholder in the company). COO Benchimol then announced he was stepping down “after an intense and hectic year” a short time after.
Sifted understands Kantor had engaged in a strategic positioning for H to enable the company to rely on its own agentic AI infrastructure. According to a source who is familiar with the topic, the project received funding offers in the billion-euro range. Sifted understands this resulted in a strategic misalignment with the board.
Whatever caused H to lose balance, insiders say any assessment of Kantor’s role should be nuanced.
“What he does is raise money. […] You can’t say he isn’t good at that,” one former H employee says. “He’s not necessarily the problem here.”
With Kantor now gone, only one of the original five cofounders, Laurent Sifre, remains at the company in the role of chief technology officer (CTO)
Kantor’s next move remains open to speculation. It might take the shape of another ambitious, record-setting project — or a break after a rollercoaster of a year.
“Charles has dined at the [presidential palace] Élysée, he’s met loads of people,” one source close to Kantor says.
“What’s certain is that he hasn’t lost much, but he’s gained a pretty stacked address book.”
Read the orginal article: https://sifted.eu/articles/h-company-charles-kantor-profile/
