• 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."

• In his 40s, Jonathan Yang decided he wanted to get hot — and stopped feeling ashamed to say it.
• His paycheck funded hair transplants, a nose job, and GLP-1s, which he continued post-layoff.
• As his body changed, he said he felt more confident and also noticed that people treated him better.

This is an as-told-to essay based on a conversation with Jonathan Yang, who was laid off from Meta in late 2024 after more than three years on the office design team. The 43-year-old shares how his job, cosmetic procedures, and weight loss shaped his confidence. The following has been edited for brevity and clarity.

At Meta, I worked really hard. I had golden handcuffs. I did not prioritize my health. You go to Meta, and they call it the "Facebook 15." Well, it was probably more than 15 pounds because of all the food that's available and all the stress. So, I just really let myself go. I put in everything I could to keep the job.

One upside was that having a bigger paycheck allowed me to start exploring things that I'd always wanted to do — emotionally, physically, aesthetically. I could finally afford a $10,000 hair transplant.

I also got a nose job. I've also had another hair transplant. Looking good and feeling good, to me, are fundamentally tied together. That's for me, and not everybody needs that. A lot of people out there are very successful being their own person and not letting that get to them. I'm not that strong.

I just wanted to get hot

Doing these things started to change how I felt about myself. It started to take away some of the shame that I had around getting aesthetic treatments. Because, as a man, it's seen as superfluous, and it's frowned upon. Before that, I had done a lot of soul-searching, therapy, and all kinds of things.

I hired a trainer, and I felt good, but the change wasn't happening fast enough. Then GLP-1s came out. I'd been waiting for something like that. I finally got on them, and then the weight started to come off, and I just started to blossom.

Once I started seeing the results, I just wanted to get hot. I wanted, at 43, to finally feel confident enough to say that out loud without having any kind of qualms about it. I think working out is a segue for people to think about improving their lives emotionally — to talk about those things — and fitness is an acceptable way for men to kind of go into that.

At work, I would get up onstage and be much more confident. Before that, it wasn't a conscious thing where I knew why I was so meek. When I look back, I would be nervous. I wouldn't smile. On GLP-1s, I started to really change and show up differently at work, and I was getting promotions. I just felt like I had more command because I lost the weight. My coworkers and managers all treated me better.

Now I'm on a lower dose of GLP-1s. I have to pay for it myself now that I'm self-employed. That's not something I'm going to stop.

People look at me differently

After my layoff, my weight was something I could control. I had to build a new routine. My body needed it, too. I had sciatica, and I had all this nerve pain. It really was like my body broke. I had never felt something like that.

I became hyper-focused on wellness, keeping fit, and eating well. Losing weight gave me the confidence to share my story. It allowed me to shed any insecurity or cringe. We say that a lot, but it was like I'm at this point now where I've only got one life to live. I know what it tastes like now.

After all the changes I made, people looked at me differently. A thing that people don't really talk about is how, on the surface, it really is about looks. I would walk into a situation with this naive sense of, "Oh, they're not looking at my weight."

As soon as I started looking more conventionally attractive, I noticed that was the first thing people would comment on. I would meet people, and they would say, "Well, you obviously go to the gym a lot," or "Oh, look at those arms!" I was like, "Wow! We live in this world where we're told, 'Aesthetics don't really matter. People look at your character.' Unfortunately, it's not true. I wish it were.

Do you have a story about how your appearance has affected your work or career? Contact this reporter at tparadis@businessinsider.com.

• Nick Woodhead said he went 48 hours without sleep while helping patch a major website vulnerability.
• The CTO said that with security problems piling up, October feels like "the month of hell" for tech.
• Because AI makes it easier to find and exploit security gaps, Woodhead expects more disruption.

This is an as-told-to essay based on a conversation with Nick Woodhead, founder of the AI company GPTree and chief technology officer at Rothco and Compubox. He spoke with Business Insider on Thursday to share how he's responded to vulnerabilities in the PHP programming language that could affect the majority of the world's websites. The following has been edited for brevity and clarity.

It's always a nightmare when these things happen. Since Tuesday evening, I haven't slept. It's coming close to 48 hours working on this. I'm a CTO, but I also run an agency for multiple clients and have my own company with my own product. So, balancing my time to get everything updated — it's just been exhausting.

About 70% of the internet runs on a programming language called PHP. I'm actively involved within the PHP community itself, so I did get a warning on Tuesday evening regarding the vulnerability and the fact that it was already being addressed by the PHP team. That gave me a head start.

I have some teams offshore, so I was able to jump on that with them.

It's not just applying the patches. It's making sure that nothing was already exposed. We already had infrastructure in place to easily deploy patches, but it still requires a good amount of manual involvement.

I knew that as soon as I walked into the office on Wednesday, I'd have to have my teams jump on this. They were already waiting for the patches to be released.

People are willing to help

One of the biggest headaches, especially on the client side, is that we have a lot of legacy systems, which are running on older versions of PHP that are no longer supported, and official patches are not going to be produced. For those, we ultimately had to come up with other plans. For example, taking sites temporarily offline or moving them behind VPNs.

Eventually, because it's an open-source community, those patches have already been backported, or implemented, by the community. So now we're shuffling back to some of those older systems to get them patched.

That's one of the nice things about PHP. There's such a vast community of people all willing to roll up their sleeves and jump in and help.

Even though I've been in leadership for the last 10 years, I've never taken my hand off the pulse in terms of being connected with the code and the infrastructure. So, I've been hands-on with the development and infrastructure teams to help make sure these issues are resolved. We've been reviewing logs and looking for any potential signatures of a breach that this vulnerability exposed.

The month of hell

It's also meant keeping up to speed with the latest news that's coming out and what other people are finding. We're in a position now where we feel comfortable and safe, but there are new vulnerabilities in the coding tool Node.js. We have some Node services, so now we're looking at how that potentially affects us. October just seems like the month of hell from a technology perspective.

I don't think there is an end in sight with the advancements in AI. For all the positives we get from it, there are a whole bunch of negatives, and this is a perfect example.

OpenAI has already stated that they found many more of these types of vulnerabilities that, thankfully, haven't been leaked. Over the coming months, they are either going to be patches or this information is going to get leaked in the same way and cause the same kind of panic.

I don't think we're at the end of the road yet. There's going to be a lot more to come.