Public company insider sells outweighed buys 10-to-1 in August

Corporate insiders at US public companies sold roughly $10 worth of shares for every $1 they bought last month, according to SEC Form 4 filings, making August the worst buy:sell ratio of the year.

Unfortunately, this month’s slightly less abysmal 1:3.6 buy:sell ratio doesn’t put September on track to improve sentiment.

Insiders have been increasingly cashing out as stock prices soar, selling high while everyone else buys high from them.

Indeed, major indices traded within 3% of all-time highs on Friday — right before Anthropic CEO Dario Amodei earned 70 million social media views over the weekend, warning that frontier AI development is moving too fast to safely control, even inside his own company.

As Anthropic increases its probability of doom or “p(doom)” to pitch investors on its next fundraise, tech and AI executives disclosed some of the year’s largest stock sales right before Amodei’s apocalyptic prediction.

Insider selling spree as probability of AI doom rises

Last week, Meta Chief Product Officer Christopher Cox sold $13 million. Joining the selling spree, CrowdStrike CEO George Kurtz sold $4.2 million on September 9 and 10.

Datadog CEO Olivier Pomel sold $18.6 million on September 8 while Cloudflare president Michelle Zatlyn sold $27.7 million from September 3 to 8.

Nvidia director Mark Stevens, over three trading days spanning August 31 to September 2, sold 1,848,501 shares for roughly $411 million.

Protos calculated that the sale beat the prior Nvidia insider selling record, Tench Coxe’s $235 million sale in September 2024, by 74%. Stevens then proposed selling up to $1 billion more.

Tech leaders joined a larger, market-wide insider selling trend. During the first half of 2026, insiders across all public sectors sold $77.6 billion worth of stock yet bought a mere $6.9 billion.

In other words, the first six months of 2026 had a buy:sell ratio of about 1:11, worse than an already terrible 1:9.7 ratio in the first half of 2025.

‘A swarm could be capable of taking over the entire internet’

According to the CEO of Anthropic, it’s probably a good thing to have sold before the end times.

“It’s my worry that in 6-12 months such a swarm could be capable of taking over the entire internet with a persistent botnet (potentially causing hundreds of billions of dollars in damage),” Amodei wrote in his viral essay this weekend that had influencers prematurely calling for a 10% drop in AI stocks.

Although Amodei didn’t warn about stock prices specifically, he pleaded, “We must slow the pace at which we improve the capabilities of AI models… Left unchecked, it could outrun our ability to understand and control these systems.”

Protos has tracked this pattern before in July. Meta insiders had just finished selling stock 150 times while buying zero shares for six consecutive months.

To be fair, nobody mentioned in this article broke insider trading rules. Sales accompanied public SEC filings, and insiders are legally entitled to liquidate for cash.

Nonetheless, the people with the best view inside public companies are converting equity into cash at a nearly 10-to-1 clip relative to any buys they made last month.

They also sold weeks prior to AI’s second-most prominent voice behind Sam Altman warning that the technology might somehow take over the internet “in 6-12 months.”