A banker wants to trade his $4.8 million California estate for shares in Anthropic. He's already gotten offers.

• The banker says he has received multiple offers from employees since posting the deal this week.
• The 13-acre Mill Valley estate features sweeping views of San Francisco, an infinity-edge pool, and a spa.
• The offer comes as Anthropic's valuation on secondary markets reached $1 trillion, and shares are scarce.

A tech banker really, really wants Anthropic shares.

The hunt for shares in Anthropic has become so frenzied in recent weeks that Storm Duncan is offering up his $4.8 million Marin County estate in exchange for stock.

"If you're going fishing, you've got to put a worm on the hook," said Storm Duncan, the founder and managing partner of Ignatious, a tech boutique investment bank, in an interview with Business Insider. "What's my other option? Not being in it?"

The offer comes as Anthropic's valuation on secondary markets soared to $1 trillion, driven by investors who have been wowed by its torrid revenue growth and momentum around its AI-powered coding assistant, Claude Code, Business Insider reported this week.

Duncan, who lives primarily in Jackson Hole, Wyo., also owns other properties, but he decided to list this one because he thought it would be especially attractive to Anthropic employees.

Duncan's 13-acre, fully furnished Mill Valley estate features sweeping views of San Francisco, an infinity-edge pool, and a spa.

"It's a 20-minute commute to the Anthropic offices in the city," he said. "No one from Anthropic probably wants my Miami or Jackson Hole place."

By offering the property, Duncan hopes to get on the radar of employees who have legitimate shares to sell and own a goldmine of Anthropic stock they can't sell until after the company goes public.

Duncan says he has received multiple offers since posting the deal this week. "Some of them are [Anthropic] employees, and some of them just happen to have invested early," he said. "I believe they're serious, but it's a complex transaction."

"There's probably a decent number of people who are sitting in a one-bedroom apartment in San Francisco even though they're earning $400,000 a year and are worth a $100 million," he said. "But they can't access that because their stock is so illiquid, so this gives them an opportunity to diversify."

It's not the first time there's been an unconventional way to secure shares in pre-IPO tech companies. In 2005, artist David Choe chose Facebook stock over $60,000 in cash to paint murals at Facebook's first office. That choice led to an estimated windfall of about $200 million once Facebook went public in 2012. In the dot-com era, some real estate owners asked startups for company stock in exchange for leasing space in San Francisco.

Some on X have dismissed Duncan's offer as a publicity stunt or a sure sign of the top of a bubble. Others have made cracks about the only thing being more precious than Anthropic shares is Bay Area real estate.

Duncan insists the offer is real and he is not seeking attention. As for why he does not simply buy shares in the company, he says a small investor like him would never be able to secure stock directly.

"Anthropic can't spend time with people like me," Duncan said. "They're looking for people who can write $100 million in a single check." (The company did not respond to a request for comment.)

The alternative is to buy shares from early employees or investors on secondary markets, but Duncan says those deals are often increasingly dubious.

He said the scarcity of shares on the secondary market has made sellers offer deals that can be rife with high fees and opaque ownership structures.

Duncan already owns shares in Anthropic that he acquired in its 2024 funding round, when it was much easier to obtain shares. He says he was recently convinced he wanted to double down after being wowed by the results of his firm's implementation of Claude Code.

"It's probably going to triple our throughput and reduce our costs by 50%," he said. "As I started to implement the platform at my own firm, I said I would like to have more exposure to this."