• Anthropic's IPO filing offers a look at a workplace where Claude does much of the coding.
• The company said it grew from 940 employees to 5,300 in less than two years.
• "Low ego" is a cultural ideal, and keeping top AI talent is a key challenge.

Anthropic is rapidly growing head count, concerned about retaining top talent, and trying to build a "low-ego" culture.

Those are among the workplace insights in the Claude maker's IPO filing released Monday.

The more than 200,000-word document reveals what it takes to thrive as an employee — or an "Ant," as staffers are called — and why the company is so focused on retaining its top talent.

Here's a look at three workplace themes in Anthropic's S-1:

Head count is booming, but could be higher without Claude

Anthropic said its workforce grew from about 940 employees at the end of 2024 to about 5,300 as of late September.

The more than fivefold spike in head count in less than two years is notable on its own. Yet, without Claude, it could have grown more. Anthropic said the tool is helping its staffers take on work that would traditionally have required much larger teams — something many tech companies are looking to do to become more nimble.

Most Anthropic employees work in research, engineering, and product development. The company said its strategy is to use Claude to grow the business "without growing head count linearly, resulting in extraordinary contributions per employee."

One place where that's evident is in software engineering. The company said these workers increasingly direct and review Claude's output rather than write code line by line. Claude wrote more than 90% of the contributions to the company's codebase in September, while average daily code contributions per engineer in the third quarter were more than 45 times their average daily level in 2024, Anthropic said.

Recruiter Martha Heller said it's little surprise to see Anthropic talking up its use of Claude. "Of course they're going to eat their own dog food," she said. In any case, Heller said, the company still needs people to provide oversight of AI's activities.

Yet the gap between staffing levels and output could grow, said Aaron Cleavinger, an executive recruiting partner at Flatiron Search Partners.

"Head count is becoming a less meaningful measure of organizational capability," he said. Cleavinger said it's not yet clear what the new measure will be, though Anthropic's approach suggests companies might put greater emphasis on workers' productivity and business impact.

It describes retention as paramount

Despite having significantly upped its employee count, Anthropic said it's highly dependent on its senior leaders and key technical team members. The company warned that their departure could disrupt operations and slow innovation.

While that's true for any employer, Anthropic faces additional challenges. It's a fast-growing startup in a booming industry, where few people have the right technical skills — and those who do are being heavily courted by competitors.

Winning the war for talent is half the battle. Anthropic is also part of an industry where some workers have quit and issued dire public warnings about the dangers of increasingly powerful AI.

For example, safety researcher Jacob Coxon resigned from Anthropic last month, saying the company and his former employer, OpenAI, were moving too quickly toward increasingly powerful AI without a sufficient plan to control it.

"That's not garden-variety turnover," said Liane Davey, an advisor on team effectiveness to executives at companies such as Amazon and Google.

If employees determine that their work poses an existential threat, no bonus can simply erase moral qualms, Davey added.

In its S-1, Anthropic said many key technical workers are motivated by its mission and by the chance to tackle specific AI problems. However, if their beliefs change, or another organization seems more aligned with their personal beliefs or professional goals, "we may face increased difficulty retaining such personnel," Anthropic said.

The company's internal data suggests that, at least for now, turnover isn't a significant problem. It said it experienced only about 1% "regrettable attrition" in a 12-month period ending on September 30.

However, Anthropic may have a thinner pipeline of junior technical talent to elevate. The company said in a recently released internal report that it has been hiring for a "smaller share of junior technical positions" as AI agents have been deployed across the firm to write code, fix bugs, and handle other tasks.

Anthropic is betting on a "low-ego" workforce

Anthropic touts a "low-ego" or "ego-light" culture, meaning all employees are expected to prioritize what's best for the company over personal status, credit, or seniority. It uses similar language on its website in a section describing its values.

In the S-1, the company went further, saying the arrangement allows for an "unusually short" distance between a research insight and a released product. Anthropic also said a shared purpose, paired with low ego, translates directly into less organizational friction and greater impact per employee.

"Our teams operate in a truth-seeking environment where the best argument wins, not the loudest voice or the most senior title," Anthropic said.

Jamie Shapiro, an organizational psychologist and CEO coach, said that logic makes sense because good ideas can come from anyone within an organization, especially those who directly interact with customers.

"An organization that has idea meritocracy is going to get the best ideas," she said.

However, as Anthropic grows, the more challenging task will be ensuring its hiring, recognition, promotion, and accountability systems reinforce its ideals — rather than allowing exceptions that undermine them.

"The bigger the organization, the harder it is to make sure everyone is living and breathing the culture it wants," said Shapiro. "Culture is defined by the worst behaviors you allow."

• Spark Capital is mentioned more than 50 times in Anthropic's S-1 filing, released Monday.
• The reason Spark gets the most mentions is because partner Yasmin Razavi has a board seat.
• Spark led the $450 million Series C round at a $4.5 billion valuation in May 2023.

Spark Capital's Yasmin Razavi has a reputation for refusing to make gut calls. Her methodical decision to invest in Anthropic is now set to generate one of the biggest fortunes in Silicon Valley history, as Anthropic prepares to IPO.

Many venture firms, including Lightspeed and Menlo Ventures, are major Anthropic investors, but Spark is the only traditional VC firm named in the filing. And it's not just a few mentions. Spark is named more than 50 times.

The reason Spark gets the most ink is because Yasmin Razavi has a board seat after being the first institutional investor in the company, leading the $450 million Series C at a $4.5 billion valuation in May 2023.

This was just six months after ChatGPT was released to the public, and the jury was out on whether a rival like Anthropic could catch up. Many balked at the price, calling it too expensive.

"It was a big leap of faith, but this was the team that built GPT-3," Razavi told Forbes.

The filing says that Spark has invested $777 million in Anthropic across six financings since then, including $75 million in the first pivotal round at $11.22 per share.

Spark was already known for making early bets on Postmates and Discord, but it was the Anthropic investment that transformed the firm's Silicon Valley reputation from a good venture firm to a great one.

Razavi said she has been continuously wowed by CEO Dario Amodei.

"Every year, he puts out outrageous numbers, but somehow they magically become true," Razavi told Forbes. "Dario never misses."

Soon, Amodei will face a greater test: the public markets.

Please send along your tips. Email Ben or Katie anytime or contact them on Signal at benbergman.11 and kroof.26. Sign up for Business Insider's weekly VC Insider newsletter here.

• Micro1 pledged to spend $1 billion on licensing companies' data for AI developers.
• The startup snags Slack messages, Canva files, Google Docs, and as much other data as it can get.
• By selling company data, CEOs have a new revenue stream that popped up this year.

As AI labs go on the hunt for real-world data, Micro1 is throwing everything at getting it for them.

The startup is one in a new class of fast-moving data brokers, gobbling up companies' internal data and packaging it for the likes of OpenAI, Anthropic, and other model developers. The executives who sell their companies' data to Micro1 find themselves suddenly participating in a new sector of the economy, where terabytes of mundane workplace interactions can be worth hundreds of thousands of dollars.

Ilya Brotzky, the CEO and cofounder of the recruiting startup VanHack, told Business Insider he was shocked when he filled out a Micro1 survey about his company's data and received a "substantial" offer.

"I didn't believe it, to be honest," he said. "I felt like it was a little too good to be true."

Micro1 says it pays $100,000 to $2 million for a single midsize company's data. It recently announced plans to spend $1 billion on the project over the next year. Brotzky and the other executives Business Insider spoke to for this story wouldn't share the exact amounts their companies received.

For Micro1, the new focus on workplace data matches a broader evolution in the industry, as Business Insider has written about in The AI Data Grab, a series about how tech giants are increasingly turning to workers, users, and the physical world to get data to train AI.

First, AI companies gobbled up text from the internet and corpora of old books. Then they realized that humans grading AI responses could improve their models. And now, companies are using complex simulations, built on real-world data, to improve the tenacity and skill of their AI.

Gartner estimated that spending on AI data is likely to surge from less than $1 billion last year to almost $6.5 billion in 2027. Micro1's chief revenue officer, William Almeida, told Business Insider in September that his company has been explaining to prospective customers why their data is suddenly so valuable for those simulations.

"Every time I talk to companies, I tell them, 'Hey, I see this as a booming business,'" Almeida said.

Slack DMs, Google Docs, Canva files: Micro1 wants all it can get

Micro1 has three ways of working with AI model developers.

First, it can take a company's raw data, transform it to protect privacy, and license it to a lab. In addition, Micro1 provides an in-progress AI agent to companies and gets feedback on how it works. The third route is the simulation: Micro1 takes a company's data up to a certain timestamp, freezes it, and then provides that "environment" to a model developer trying to teach its AI how to work from existing context.

Micro1 pays more for larger, more complex datasets, as well as for data that represents a unique type of work or knowledge. It usually wants to license a company's entire data corpus, so that an AI model can replicate what it would be like to be a human employee.

"The connection, the diversity, the traceability of all of these data points, they matter a lot when you think about model training," Almeida said.

Brotzky also received an offer from AI data startup Mercor to buy his company's data, though he opted for Micro1. Once Brotzky dug into Micro1's privacy process, he said he felt comfortable sharing all the data they requested. That included VanHack's Google suite, Confluence data, Slack messages, and customer relationship management software.

Grant Gooley, the CEO of the marketing agency MyPortal Marketing, also views his deal with Micro1 as an innovation. He has sold internal design files from Figma and Canva, as well as checklists from Monday.com.

"When we were building these processes years ago, I didn't think that we would be using it to support AI learning," Gooley said. "But doing that, it's very fulfilling."

CEOs pitch the deals to their workers

Micro1 and its rivals are full steam ahead. Still, there are open questions. Former and current employees aren't likely to get any compensation from — or a voice in — their work becoming AI fodder. Ifeoma Ajunwa, a law professor at Emory University, previously told Business Insider that data sales are an "ethically gray area."

When pitching to potential customers, Almeida tells them this business is in the early days.

"If you wait too much, you won't get the premium that the first companies are getting," he said.

VanHack's team got a confidence boost from the Micro1 deal, Brotzky said, because of the additional revenue stream it represents

Gooley said he's kept MyPortal Marketing's employees in the loop about the deal with Micro1 and hasn't heard any complaints.

"I told my team that this is something that you're going to tell your grandchildren about one day, because we are literally supporting the future growth of marketing agencies," Gooley said.

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