Two associates of Sam Bankman-Fried invested in Anthropic. After they were sentenced for fraud, their shares entered a legal black hole. ANGELA WEIS/Getty Images; Tyler Le/BI

A little over a year ago, the federal government acquired a stake in Anthropic without paying a penny.

The shares were seized from associates of the crypto fraudster Sam Bankman-Fried . From there, they disappeared into a legal black hole.

As Anthropic rockets toward what could be the biggest IPO in history , those shares could now be worth billions of dollars.

Bankman-Fried's own Anthropic stake was liquidated in the bankruptcy of his failed cryptocurrency exchange. The Anthropic equity owned by Caroline Ellison and Nishad Singh, two associates who invested alongside him, took a different path.…