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Another xAI cofounder, Manuel Kroiss, has told people he is leaving Elon Musk's company.
Just one cofounder out of 11 remains besides Musk.
The company has been in flux ahead of a widely anticipated IPO at SpaceX, which recently acquired xAI.
And then there was one.
XAI cofounder Manuel Kroiss has told people he is leaving the company, according to insiders with knowledge of his exit.
Kroiss, who is also known as "Makro," is one of 11 engineers who helped launch the company alongside Elon Musk in 2023. With his exit, the number of cofounder departures now sits at 10.
Guodong Zhang, Zihang Dai, Toby Pohlen, Jimmy Ba, Tony Wu, and Greg Yang have all stepped away since January.
XAI and Kroiss did not immediately respond to requests for comment.
Kroiss led pretraining, which helps train the company's AI models on large datasets, and reported directly to Musk. He also worked on improving xAI's coding models alongside Zhang, who left earlier in March. Musk said at the Abundance Summit earlier this month that xAI is "behind in coding," but the company is working to "exceed our competitors on coding."
Before joining xAI, Kroiss worked at Google and DeepMind.
Ross Nordeen, who came to xAI from Tesla, is the only remaining cofounder aside from Musk.
The company's organizational structure has been in flux over the past few weeks, according to people with knowledge of the changes. Musk has taken over managing dozens of direct reports and has brought in workers from Tesla and SpaceX. It has also shed dozens of employees, the people said.
Earlier this month, Musk said on X that "xAI was not built right first time around, so is being rebuilt from the foundations up."
He has also said that the company is resifting through old xAI candidates to bring in new people.
"Many talented people over the past few years were declined an offer or even an interview @xAI," Musk wrote on X.
Musk's rocket company, SpaceX, acquired xAI earlier this year. The company is expected to file an initial public offering this year, which could value it at $1.5 trillion.
OpenAI has become a centerpiece in the AI talent wars, data reviewed by Business Insider shows.
Workers often leave Big Tech for Sam Altman's venture and then move on to smaller startups.
The average tenure for US-based OpenAI employees is around 16 months.
Workers leave Big Tech for OpenAI. They fan out across a growing ecosystem of startups. Rinse and repeat.
Since it launched ChatGPT, the Sam Altman-led company has quickly become a magnet for AI talent. It has pulled hundreds of researchers and engineers from competitors like Google, Meta, and Apple, according to data reviewed by Business Insider. After sticking around for a while, many of those employees go on to found or join rival startups of their own.
The company has nearly quadrupled in size since its chatbot took off in 2023, scaling from a small research lab of around 1,000 employees to a tech company with more than 4,000 workers.
To get a sense of how OpenAI is faring in the race for AI talent, Business Insider analyzed findings from workforce intelligence provider Live Data Technologies, which used LinkedIn to track the comings and goings of around 1,300 employees from January 2023 to March 2026.
Live Data Technologies analyzed publicly available professional profile data for OpenAI employees who had available information on previous employers. The roles analyzed ranged from engineering and research to product, human resources, and recruiting.
Representatives for OpenAI didn't respond to a request for comment.
The company's hiring pipeline is highly concentrated
OpenAI was originally founded by Altman and Elon Musk in 2015 to compete with Google's DeepMind AI lab.
Now, Google is the No. 1 source of talent for OpenAI, accounting for roughly a quarter of hires, according to the data.
Nearly half of OpenAI hires in the last three years came from either Google, Meta, Apple, or Microsoft.
Apple's Jony Ive joined OpenAI last summer to work on a new AI device. The project encompasses around 300 workers, many of whom came from Apple, The Information reported earlier this year.
The company has also made several high-profile hires over the past year, including Slack CEO Denise Dresser, OpenClaw founder Peter Steinberger, and Instacart CEO Fidji Simo.
Since 2023, OpenAI has added roughly four times as many engineers as it has lost, highlighting the company's rapid expansion as the AI race intensifies.
The battle for AI talent has become one of Silicon Valley's fiercest. Big Tech companies are aggressively competing for a relatively small pool of researchers capable of building advanced AI systems.
Meta CEO Mark Zuckerberg has reportedly taken a hands-on role in recruiting top AI employees, while Meta and other companies have reportedly offered massive compensation packages, sometimes valued in the tens and hundreds of millions of dollars in stock.
OpenAI is known for its high compensation packages. The Wall Street Journal reported last year that its employees receive an average of $1.5 million in stock-based compensation. Public salary data from H-1B visa applications shows that research scientists at the AI venture have salaries ranging from $245,000 to $685,000, while engineering roles are listed with a range of $165,000 to $290,000.
Where employees go after OpenAI tells a different story
Departures are fragmented, spreading across more than 150 different companies, including competitors like Meta, Anthropic, and emerging labs such as Thinking Machines Lab, according to the data. The majority of OpenAI employees left for smaller startups, venture capital firms, or academia, according to the data.
The data suggests OpenAI has become a centerpiece in the AI talent network, pulling researchers from Big Tech and sending alumni across the startup and VC ecosystem.
Only a handful of companies received more than 15 OpenAI alumni in the last three years: Anthropic, Meta, Google, and Thinking Machines Lab, the data shows.
Anthropic is perhaps the best-known example. It was founded by former OpenAI researchers, including siblings Dario and Daniela Amodei. VP of Research Max Schwarzer left OpenAI for Anthropic earlier this month.
Meanwhile, several OpenAI employees who left the company to help found Thinking Machine Labs in February, including Barret Zoph, rejoined OpenAI earlier this year.
Common roles at OpenAI include engineering and research, the data shows. The average tenure for US-based OpenAI employees is around 16 months.
OpenAI has built one of the most popular products in the world. Now it has to figure out how to pay for it.
Enter Fidji Simo.
Simo, the 40-year-old former Instacart CEO and longtime Meta executive, became OpenAI's product boss in August under CEO Sam Altman. While Altman has long been the face of OpenAI, Simo is increasingly shaping how the company operates and makes money.
"Part of bringing me on, and giving me the responsibilities of a CEO, was to make sure that I could really run that part of the company with autonomy," Simo, whose title is CEO of applications, told Business Insider.
Altman defers to Simo when he doesn't feel strongly, she said, and they "debate it out" when he does.
As OpenAI races toward a possible IPO later this year, Simo, who oversees nearly two-thirds of the company, has a delicate balancing act. She must craft a strategy to make products profitable, while convincing staffers who joined a research-driven organization that commercialization won't change the mission.
The stakes are high. Deutsche Bank estimated that OpenAI is expected to amass the "largest startup losses in history," totaling a projected $143 billion between 2024 and 2029. (An OpenAI spokesperson said that figure is incorrect, and one person familiar with the numbers said OpenAI's internal projections are in line with other reports of $111 billion cash burn by 2030.)
Competitors like Anthropic and Google are starting to erode OpenAI's early and commanding lead and, in some cases, surging ahead. Anthropic's coding tool has outperformed OpenAI's even after the latter made dominance in coding its top priority, a person familiar with internal goals told Business Insider.
OpenAI and Simo now face pressure to create the most powerful models and turn them into accessible and marketable products that can sustain the enormous cost of training and deployment.
"This AI moment is so unique that there is really no blueprint for OpenAI to follow," UBS analyst Karl Keirstead told Business Insider. "This is uncharted territory."
In an interview, Simo was warm and charismatic — a charm paired with a reputation for intensity and follow-through. This month, she unveiled a strategy shift for the company: an increased focus on coding and enterprise users.
"We cannot miss this moment because we are distracted by side quests," Simo told employees at an all-hands meeting, according to a person familiar with her remarks. The company needs to nail productivity — primarily on the business side, and then on the consumer side, she said. "Everything else is going to have to take a backseat to those priorities."
Former colleagues said they were familiar with this laser focus.
One former Meta employee recalled a moment when, after a contentious meeting, Simo sent a one-line follow-up saying she was unlikely to change her mind, so the team shouldn't waste time trying to persuade her. She has little patience for internal debates that lose sight of the product, the former employee said, and she's skilled at "being super clear in her directive so teams don't scramble and waste time."
Priya Monga, who served as Simo's chief of staff at Facebook and Instacart and is now director of go-to-market strategy at Instacart, said Simo arrives at any new role having mapped out the full journey.
"She knows she's going from A to Z, and she sees that right at the beginning," Monga said. "In the back of her mind, she has already really thought a lot about the broader visionary 10-year road map."
Interviews with Simo, current and former OpenAI employees, and former colleagues reveal how she's approaching one of the company's most crucial years — and the mark she's already made on it.
Competing for resources
A few months after she joined OpenAI, Simo invited the company's researchers to a series of roundtable meetings.
She wanted to talk about advertising inside the AI giant's flagship product, ChatGPT: what it might look like, what guardrails should be in place, and what principles would make AI ads publicly defensible. Nearly 100 employees weighed in.
For years, OpenAI executives said the company wouldn't turn to ads for revenue. Altman referred to the idea as a "last resort." A year later, Altman hired Simo, a seasoned executive with a reputation for monetizing new products. In February, OpenAI began testing ads.
The drive to become more product-focused predated Simo, two people familiar with the company's internal strategy told Business Insider.
After ChatGPT took off in 2023, OpenAI leaders decided to put research teams in two buckets: one for improving products, and another centered on more forward-looking exploratory projects. In the years since, the company has faced more pressure to roll out products as competitors gained ground.
OpenAI had two broad goals in 2025, according to a former executive: reach a $12 billion revenue run rate, which it handily beat midway through the year, and "dominate in AI coding," which it did not. It was the first time the company had failed to meet a major internal objective, according to the person familiar with the goals.
Codex, OpenAI's coding tool, has since reached more than 2 million weekly active users, nearly four times as many as at the start of the year. Anthropic doesn't disclose active users; it said in February that Claude Code's run rate revenue is more than $2.5 billion, and its weekly active users had doubled since January 1.
OpenAI leadership realized it needed to start acting more like a Big Tech company, not a research lab. "There's definitely some stress happening to the company, and no company wants to be behind," one of the people familiar with the company's strategy said.
Since Simo joined, OpenAI has moved several executives into different roles, two people with knowledge of the shifts said.
Simo joined OpenAI after stints at Instacart and Meta.
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A few months after she arrived, Kevin Weil moved from chief product officer to vice president of OpenAI for science, and VP of engineering Srinivas Narayanan became chief technical officer of B2B applications. In January, Chief Operating Officer Brad Lightcap shifted to overseeing commercial operations, while Barret Zoph began overseeing B2B after he rejoined the company. Weil and Narayanan underwent title changes in September, according to their LinkedIn profiles.
Simo has also personally recruited a number of high-level executives from across Big Tech, including former Facebook VP Vijaye Raji, Slack CEO Denise Dresser, OpenClaw founder Peter Steinberger, and several executives from Amazon, Shopify, and Instagram, according to a person familiar with the leadership changes.
Since Simo started, the company's post-training team, which fine-tunes AI models after initial training, has acted as a bridge between research and product teams. The team interfaces directly with Simo about research projects, a person with knowledge of the organizational strategy said.
Early on,Simo told Business Insider, she did a "listening tour." More than 200 people took up her offer to meet, she said. That helped her better understand the company and culture and build trust with her new colleagues.
"I think that really made the company feel like I wasn't jumping in with preconceived notions," she said. "I was really trying to understand what was right for this company at this specific moment in time."
Simo said she manages the company's product research team alongside Mark Chen, the company's chief research officer. One of her first priorities was to understand how the research side operated, something she worked closely with Chen on.
As ChatGPT grows — it has nearly a billion weekly users — and its valuation surges, resources like compute power — the GPU chips, energy, and data-center capacity required to train and run AI models — have become increasingly competitive.
The tension between research and product has become increasingly visible inside OpenAI, some insiders say. Some researchers told Business Insider that the focus on user optimization and product growth risks narrowing the lab's ability to chase more exploratory work.
Earlier this year, vice president of research Jerry Tworek resigned after seven years at OpenAI, saying in a post on X that he wanted to "explore types of research that are hard to do at OpenAI."
Others have voiced similar frustrations. Tom Cunningham, the company's chief economist, left in December over friction between OpenAI's work on the economic impact of AI and the marketing of its product, Wired reported at the time.
One former researcher told Business Insider that as ChatGPT has grown, they "started feeling a little bit of pushback" from the rest of the company and began to feel as if "ambitious research" didn't have a place at the company anymore. Another former employee said the pivot towards a more traditional tech culture at OpenAI was "inevitable," but it has led to a "changing of the guard."
"At the end of the day, it's about survival," they said.
Chen has pushed back against claims that the company is driving a product-focused agenda. "The majority of our compute is allocated to foundational research and exploration — and not product milestones," he wrote on X in February.
Are we going to turn into Big Tech?
Simo was hired by OpenAI after serving on the board for more than a year.
Some employees, Simo told Business Insider, worried that her arrival meant OpenAI would transform into a Big Tech clone. "Is the only way to build this big product company to hire tons of people and kind of do what Big Tech is doing?" she recalled employees asking.
She spent her first few months trying to convince them that the answer was no.
One of her early moves was a company-wide effort to eliminate the unnecessary bureaucracy that can bog down a large organization. She publishes a monthly update on the company's Slack detailing obstacles that have been removed — everything from small annoyances like how to get headphones to bigger structural bottlenecks like clunky code reviews. She created a dedicated inbox where employees could flag issues and says she reads every submission.
"I'm very focused on scaling the company without creating the excess process and friction that many of us have seen in big tech," read an excerpt of her first dispatch.
Her aim, she said, is to keep OpenAI small, focused, and process-light. To that end, Simo said, OpenAI has an advantage that most Big Tech companies don't: It started as a research lab.
"There is no product if there is no research," Simo said. It's easier to build products on top of a strong research base than to put a research lab on top of a product-driven company, she added.
Big Tech would "put products out into the world and then kind of react to what would happen," Simo said. "We started with a research lab that was very focused on safety, and really thought of safety as a leading research field and not as the thing you do right before the launch."
"I think we have a very big advantage in how we think about problems and anticipating where the technology is going and feeling a lot of responsibility for guiding that technology towards the right place," she added.
Vivek Sharma, who worked under Simo at Meta, said that's a natural part of the maturation process in tech.
"Tension is a good sign someone is advancing beyond the basics," he said. "If there's no tension, no division happening — real expertise, experience, past multi-domain decisions haven't been made."
'Founder mode'
Simo isn't a traditional Silicon Valley insider. Raised in Sète, a fishing town on France's Mediterranean coast, she was the first in her family to graduate from high school before earning a place at one of France's elite business schools.
From there, she worked her way into tech — first through an internship at eBay, then at Facebook, where she went on to help monetize the company's core app and eventually oversee some of its most ambitious product expansions. She also served as CEO at Instacart, where she helped steer the company through the pandemic boom and took it public in 2023 during a notoriously difficult market for tech IPOs.
Simo married her high school sweetheart, former software engineer turned chocolatier Remy Miralles, in 2011; they have a young daughter. Simo has spoken in the past about how navigating chronic health issues, including endometriosis and the nervous system disorderPOTS, has shaped some of her work. She cofounded a women's health venture called the Metrodora Institute and was largely responsible for the launch of ChatGPT Health.
Former colleagues describe Simo as intense, empathetic, and known to crack a joke during a high-stakes meeting.
They say that background shapes how she leads. Sharma described her as a "hard-charging" executive with a distinctly human lens — someone who thinks about what ordinary people would actually find useful, not just what's technologically impressive.
Nick Turley, the head of ChatGPT who reports to Simo, said she has a "customer orientation" that has reshaped how the company approaches products. During an interview, he said that she has driven a new focus on reliability and performance over "flashy" new tech.
She also has a relentless operating tempo. Turley described it as her propensity to go "founder-mode."
"She will read every single document — including the links," he said.
Daniel Danker, who worked with Simo on Facebook's video team and later at Instacart, said "she was causing all of Facebook to move faster."
Simo's track record of commercialization is not without controversy.
At Instacart, Simo inherited a fraught relationship with gig workers. On her first day as CEO in August 2021, she published an open letter pledging to be "a thoughtful and open partner" to the company's hundreds of thousands of gig workers, and invited them to email her directly.
The Gig Workers Collective, representing some 13,000 contract workers, called for a boycott and walkoff within weeks, telling Fortune that her responses were "basically canned answers."
OpenAI's next chapter
At OpenAI, Simo has helped push several high-profile initiatives, including a newsletter product called ChatGPT Pulse, OpenAI's Frontier enterprise agents, and advertising. This month, the company launched GPT-5.4, a model that incorporates coding capabilities into its core system, and announced a desktop "superapp," which Simo will oversee.
Simo said she approaches new product launches by involving employees throughout the process. She pitched those advertising roundtables by sharing her own ideas for what kind of ads the company could be proud of, and asking employees to share where they agreed and disagreed.
"The way I approached it was not to tell the company we're going to have ads. It's to actually start a dialogue," Simo told Business Insider. "That's not usually the way it goes. That's a big difference for this place."
As product chief, Simo has to prepare the company for battle inside a complex leadership structure, working closely with Altman.
Sam Altman, OpenAI's CEO.
Justin Sullivan/Getty Images
Simo has said the two are complementary and aligned on vision, with Altman focusing heavily on research and compute scaling while she drives product execution.
It's a dynamic familiar to Simo, who worked closely with Mark Zuckerberg. She had a special talent for knowing how to navigate the CEO, Sharma said.
OpenAI can be a cutthroat place to work for leaders. As one former executive put it, OpenAI is such a rocket ship that there's very little time or patience for those who don't hit the ground running. "What a leader needs to do is astounding," the person said.
"The speed at which OpenAI is growing, it's relatively easy for Sam to hire the best, most famous people, but it's hard to keep them. His mode is: Nobody is not sacrificeable," the person said. "'You have to magically grow to what I think you can do right now.'"
OpenAI no longer has the luxury of being a research lab dreaming about the future of AI. It has rapidly become a global consumer product under intense scrutiny. Now Simo's job is to help it grow up without losing what made it successful in the first place.
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