Bitcoin price (BTC) slides alongside software stocks following leak of new Anthropic model - CoinDesk

Markets Share Anthropic’s massive 'Claude Mythos' leak sends software names — and crypto — sharply lower The model could significantly heighten cybersecurity risks by rapidly finding and exploiting software vulnerabilities, potentially accelerating a cyber arms race. By Helene Braun|Edited by Stephen Alpher Updated Mar 27, 2026, 10:14 a.m. Published Mar 27, 2026, 9:56 a.m. Make preferred on (Michael M. Santiago/Getty Images) What to know: Anthropic is testing a new AI model, internally dubbed "Claude Mythos," that it describes as a major step up in capability from its existing systems. Leaked internal documents warn the model could significantly heighten cybersecurity risks by rapidly finding and exploiting software vulnerabilities, potentially accelerating a cyber arms race. The iShares Expanded Tech-Software Sector ETF (IGV) is down nearly 3% early Friday, likely contributing to bitcoin's tumble back to $66,000. Anthropic, the artificial intelligence company behind Claude, has begun testing a new AI model more capable than any it has released previously, Fortune reported. The company said the model represents “a step change” in performance and is “the most capable we’ve built to date.” It is currently being tested with a small group of early access customers as Anthropic evaluates its behavior and risks. Among the names moving sharply lower on the news: Palo Alto Networks (PANW), Crowdstrike (CRWD) and Fortinet (FTNT) are all down 4%-6%. The broader iShares Expanded Tech-Software Sector ETF (IGV) is off 2.5%. The overnight leak likely contributed to bitcoin's BTC $66,431.75 tumble back to $66,000 after flirting with $70,000 hours earlier. Details about the model surfaced after internal materials were accidentally exposed in a publicly accessible data store, according to Fortune. Around 3,000 assets linked to Anthropic’s blog were available online, including draft announcements and internal content that had not yet been released. Among the files was a draft blog post referring to the model as “Claude Mythos.” The document warned that the system could pose serious cybersecurity risks, pointing to its ability to identify and exploit software vulnerabilities. Anthropic currently offers three tiers of models — Opus, Sonnet and Haiku — which vary in size, cost and capability. The leaked materials suggest the company is developing a new tier called “Capybara,” which would be even larger and more intelligent than Opus, the company’s most advanced model to date. Artificial Intelligence More For You The Definitive Stablecoin Landscape Series: North America By CoinDesk Research Mar 26, 2026 Commissioned byRipple As stablecoins evolve into core financial infrastructure, North America leads. This report maps the regulation, market shifts, and players driving adoption. Why it matters: Stablecoins are entering their third phase of evolution - the institutionalization era - becoming increasingly embedded into core financial infrastructure. As institutions prioritize transparency and compliance, regulated issuers like USDC, RLUSD, and PYUSD are steadily gaining share with RLUSD surpassing $1B in market cap within its first year. North America, leading in regulatory frameworks and institutional distribution, is at the center of it all. View Full Report Strategy may have paused bitcoin accumulation last week, ending a thirteen week buying streak By James Van Straten|Edited by Aoyon Ashraf 1 hour ago The company seemed to have skipped it's weekly bitcoin purchase announcement for the first time since late december. What to know: Strategy appeared to make no bitcoin purchases last week, after a run of 13 consecutive weekly buys. MSTR is down about 77% from its peak in November 2024. Read Full Story Latest Crypto News Stablecoin payments go 'invisible' in Southeast Asia as crypto card business surges 1 hour ago Strategy may have paused bitcoin accumulation last week, ending a thirteen week buying streak 1 hour ago No one is 100% happy with the stablecoin yield agreement: State of Crypto 2 hours ago Bitcoin bullish bets hit a 28-month high on Bitfinex, and that's music to bears' ears 3 hours ago Crypto's CLARITY Act could be a headwind for DeFi tokens ring-fencing yield, analyst says 4 hours ago Markets move to price in rate hikes as inflation fears and geopolitics reshape Fed expectations 4 hours ago Top Stories Bitcoin miners are becoming AI companies and selling their BTC to fund the transition Mar 27, 2026 Crypto stocks battered as Nasdaq enters correction in $17 trillion market rout Mar 27, 2026 Canada moves to ban crypto donations for election campaigns following UK Mar 28, 2026 Bittensor ecosystem tokens' value hit $1.5 billion as Jensen Huang endorsement supports TAO rally 6 hours ago New Ethereum project aims to fix network fragmentation and improve user experience 5 hours ago Here's what next as Anthropic's most powerful AI model leaked via unsecured data cache Mar 28, 2026 In This Article BTC $66,431.75 ◢0.69%