An artificial intelligence model developed by Anthropic has resolved a cryptographic puzzle that had confounded researchers for 25 years, tracing a set of numbers at the heart of widely used encryption standards to an ordinary computer program.

According to Anthropic, its Claude model traced five curve seeds supplied by the U.S. National Security Agency (NSA) to a basic random-number generator in less than 30 minutes. The seeds are starting values for the elliptic curves adopted in 2000 by the U.S. National Institute of Standards and Technology (NIST), which are used in digital signatures across widely deployed cryptographic standards. The NSA supplied the seeds but never explained how it chose them, and some researchers feared the agency had tested many options to land on a curve with a hidden weakness. The answer carries weight because elliptic-curve cryptography secures digital signatures across web traffic, software updates, and many other widely used systems — the checks that let computers confirm a website or a piece of software is what it claims to be.

Anthropic detailed the work in a research note. An employee asked an internal research model to examine the problem earlier this month, and the company said Claude completed the task in under half an hour. The result resolves a question that had resisted both public efforts and official records requests for more than two decades.

CLAUDE SOLVES 25-YEAR-OLD MYSTERY SURROUNDING NSA CRYPTOGRAPHIC STANDARDS Anthropic researchers report that Claude solved a decades-old mystery surrounding the origins of the NIST elliptic curves used in widely adopted cryptographic standards. For more than 25 years,…

— Bitcoin News (@BitcoinNewsCom) October 16, 2026

What Claude found

Claude traced the five seeds to lrand48, a random-number generator found in older C software libraries. The program produced the values using timestamps from 1997 and 1998. In its search, the model matched the published seed for the P-256 curve at the 1,842nd candidate, and anyone can now rerun the program to arrive at the same numbers. That reproducibility means the conclusion no longer rests on trusting either the agency or the model: the claim stands on a computation whose output anyone can verify.

Anthropic said the result makes it more confident that the curves were chosen without backdoors. Questions remain, however, about why the program skipped some usable candidates and how other parts of the curves were picked — loose ends that any future examination of the curves’ construction would need to address. The company said people who use the NIST curves do not need to change anything, while acknowledging that the finding does not fully rule out deliberate manipulation.

The effort carried a bounty of $36,864, offered since 2023 by engineer Filippo Valsorda and other contributors. The reward will go to the Internet Security Research Group, the nonprofit behind Let’s Encrypt.

Earlier attempts to solve the mystery had failed. Researcher Steve Weis filed public-records requests in 2018, and NIST said it held no documentation. Jerry Solinas, the NSA mathematician who supplied the seeds, died earlier in 2023, leaving no firsthand account of how the values were chosen.

What it means for Bitcoin

Bitcoin does not use the NIST curves. The network relies on secp256k1, a curve defined by two small, fixed numbers that leave little room to hide a weakness. Satoshi Nakamoto never publicly explained the choice, and Ethereum later adopted the same curve.

Ledger co-founder Nicolas Bacca reacted to the news with the remark “checkmate Satoshi,” while Blockstream CEO Adam Back pushed back and blamed the NSA for failing to explain its choices.

Claude found no weakness in Bitcoin, and the network’s cryptography remains secure against known practical attacks. Quantum computing stands as a separate long-term concern. Google said this week that its Willow chip cut errors roughly 40-fold in one of the costliest steps a quantum machine would need to perform, though no computer yet exists that is large or reliable enough to crack a bitcoin key.