Claude Fable 5.1 September 1, 2026 (12 days ago) ( 2026-09-01 ) September 1, 2026 (12 days ago) ( 2026-09-01 ) Claude Opus 5 July 24, 2026 (51 days ago) ( 2026-07-24 ) July 24, 2026 (51 days ago) ( 2026-07-24 ) Claude Sonnet 5 June 30, 2026 (2 months ago) ( 2026-06-30 ) June 30, 2026 (2 months ago) ( 2026-06-30 ) Claude Haiku 4.5 October 15, 2025 (10 months ago) ( 2025-10-15 ) October 15, 2025 (10 months ago) ( 2025-10-15 ) Large language model Generative pre-trained transformer Foundation model Claude is a series of large language models (LLMs) developed by American software company Anthropic . Claude was released as an AI -based chatbot in March 2023. It is also used in AI-assisted software development . Anthropic sells Claude-based agentic tools including Claude Code, a terminal coding agent, and Claude Cowork, a similar tool for non-programmers. Claude is trained using a constitution , a technique developed by Anthropic to improve ethical and legal compliance. Since Claude 3, each generation has typically been released in three sizes, named Haiku (the least capable), Sonnet, and Opus (the most capable). In 2026, an additional model named Claude Mythos was released to a handful of companies and organizations; this was followed by the release of Claude Fable , a version of Mythos with stricter safeguards, to the general public. In February 2026, the United States Department of Defense designated Anthropic a "supply chain risk" and federal agencies were ordered to phase out Claude after the company refused to remove contractual prohibitions on using Claude for mass domestic surveillance and fully autonomous weapons . [ 1 ] A federal judge blocked the designation in March 2026 and permanently set it aside in August 2026 as unconstitutional retaliation. [ 2 ] [ 3 ] Claude is a generative AI chatbot. [ 4 ] It sometimes uses artifacts, a feature introduced in June 2024 to generate and interact with code snippets and documents. [ 5 ] [ 6 ] In 2025, Anthropic added a web search feature to Claude. [ 7 ] [ 8 ] Claude Pro and Claude Max are subscription services for additional access to Claude models. Max provides higher usage limits at an additional cost. [ 9 ] Grouped subscriptions include Claude Team and Claude Enterprise. [ 10 ] According to card-spend data from Ramp , the share of businesses on its platform paying for Anthropic products rose 4.9 percentage points in February 2026, to 24.4%, the largest monthly gain Ramp had recorded for the company. [ 11 ] [ 12 ] A Claude feature allows users to share chats with anyone who has the link. [ 13 ] In September 2025, Forbes reported that hundreds of shared Claude chats had appeared in Google Search results, following similar incidents involving OpenAI's ChatGPT and xAI's Grok . [ 14 ] In July 2026, shared chats and Artifacts were again found to be indexed by Google. The BBC counted more than 200, some containing health records and corporate documents. [ 13 ] [ 15 ] The affected chats were those whose links had been posted on the public internet. Technical analysis suggested that a robots.txt rule blocking crawlers from shared-chat pages also prevented them from reading the noindex directive meant to keep the pages out of search results. [ 16 ] Anthropic said the listings had been removed. [ 17 ] Application programming interface Claude is also provided through an application programming interface (API). In October 2024, the "computer use" feature was introduced by which an application can call the Claude API to attempt to give navigational control of the application via Claude's interpretation of screen content and simulation of keyboard and mouse input. [ 18 ] Claude Code, released in February 2025, is an agentic command line tool to delegate coding tasks from the terminal using natural language prompts. [ 19 ] It was made generally available in May 2025 alongside Claude 4. [ 19 ] [ 20 ] Based on enterprise adoption, Anthropic reported a 5.5x increase in Claude Code revenue by July. [ 21 ] On October 20, 2025, Anthropic launched a web version of Claude Code and a sandboxing feature. [ 22 ] Coinciding with performance improvements tied to Claude Opus 4.5, Claude Code went viral during the 2025–2026 winter holidays when people had time to experiment with it, including many non-programmers who used it for vibe coding . [ 23 ] [ 24 ] [ 25 ] In August 2025, Anthropic reported that cybercriminals it designated "GTG-2002" had used Claude Code in a data-extortion campaign against at least 17 organizations. [ 26 ] In November 2025, Anthropic said that in September a China-based cybercrime group had used Claude Code to automate 80–90% of its espionage cyberattacks against 30 organizations. [ 27 ] [ 28 ] [ 29 ] Claude Code is used by Microsoft, [ 30 ] Google, [ 31 ] and was used by OpenAI employees until August 2025, when Anthropic revoked OpenAI's API access, calling it "a direct violation of our terms of service". [ 32 ] In February 2026, Anthropic introduced Claude Code Security, which reviews codebases to identify vulnerabilities . [ 33 ] In March 2026, the source code for the Claude Code command-line interface application was leaked, revealing multiple upcoming features and models. [ 34 ] [ 35 ] In May 2026, Anthropic introduced "Dreaming", a research-preview feature of its Managed Agents API that consolidates an agent's persistent memory between sessions by merging duplicates and removing stale entries; [ 36 ] [ 37 ] a memory consolidation feature called autoDream had been identified in the March source code leak. [ 38 ] Claude in Chrome In August 2025, Anthropic released Claude for Chrome, a Google Chrome extension that lets Claude browse websites, click and fill forms on the user's behalf. It launched as a pilot for 1,000 Max subscribers. Anthropic said prompt-injection attacks succeeded 11.2% of the time after mitigations. [ 39 ] It became generally available in August 2026. [ 40 ] Claude Cowork is a tool similar to Claude Code but with a graphical user interface , aimed at non-technical users. It was released in January 2026 as a "research preview". [ 41 ] [ 42 ] Cowork is available as a desktop application for Mac and Windows and through a web interface. [ 43 ] It provides Claude with access to a sandboxed shell and to user-selected folders on the local file system, allowing the model to read, write and edit files, execute code, and chain multi-step tasks within a single conversation, such as organizing files on a user's computer or generating documents from material in a local folder. [ 44 ] [ 45 ] A Wall Street Journal reporter who tested the tool noted user concerns about granting an AI agent broad access to a personal computer. [ 45 ] An early user reported that, after asking Cowork to organize the files on the desktop of his wife's computer, it deleted all the family photos requiring the restoration of the images from an iCloud backup. [ 46 ] [ 47 ] In February 2026, Anthropic announced a wider enterprise release of Cowork, adding connectors for services such as Google Drive , Gmail , Docusign and FactSet , and customizable plugins for domains including financial analysis, engineering and human resources. The company described the update as a transition into an "enterprise-grade product". [ 48 ] In March 2026, Anthropic added Dispatch, which lets users send Cowork tasks from a phone to their computer, and allows Claude to operate programs on the user's computer, such as web browsers or spreadsheet applications, to carry out tasks. [ 49 ] According to developers, Cowork was mostly built by Claude Code. [ 42 ] In August 2026, Cowork was made available in a sidebar of the Chrome browser. [ 50 ] Claude Design is a tool released by Anthropic as a preview for paying customers on April 17, 2026. It generates designs, prototypes, slides and marketing materials from natural-language prompts, is uses Claude Opus, and can export to multiple formats. [ 51 ] Announced on June 30, 2026, the Claude Science service was released in public beta to paid subscribers, with an emphasis on biology research and drug development . [ 52 ] [ 53 ] Claude models are generative pre-trained transformers that have been trained to predict the next word in large amounts of text. Then, they have been fine-tuned using reinforcement learning from human feedback (RLHF) and constitutional AI in an attempt to enforce ethical guidelines. [ 54 ] [ 55 ] ClaudeBot searches the web for content. It was criticized by iFixit in 2024 for accessing their site over a million times a day to scrape content without permission, and also for the resulting excessive load on their system. [ 56 ] [ 57 ] Constitutional AI Anthropic introduced an approach to AI alignment called "Constitutional AI". The constitution is a document used to train Claude to be harmless and helpful without relying on extensive or expensive human feedback. [ 58 ] Time described this constitution as "somewhere between a moral philosophy thesis and a company culture blog post". [ 59 ] The original version was a list of principles. [ 59 ] The first constitution for Claude was published in 2022. The 2023 update listed 75 guidelines for Claude to follow. [ 54 ] [ 60 ] The first constitutions included concepts taken from the 1948 UN Universal Declaration of Human Rights . [ 59 ] [ 58 ] The 2026 version includes more thorough explanations for how Claude is intended to behave and why, and has 23,000 words, an increase from 2,700 in 2023. [ 61 ] Claude models are usually released in four sizes: Haiku, Sonnet, Opus, and Mythos/Fable (from smallest and least expensive to largest and most expensive). Claude is reportedly named after Claude Shannon , a 20th-century mathematician who laid the foundation for information theory . [ 71 ] The first version of Claude was released in March 2023. [ 64 ] It was available only to selected users approved by Anthropic. [ 72 ] Claude 2, released in July 2023, became the first Anthropic model available to the general public. [ 72 ] Claude 2.1 doubled the number of tokens that the chatbot could handle, increasing its context window to 200,000 tokens, which equals around 500 pages of written material. [ 66 ] With the release of Claude 2.1, Anthropic also introduced the then-beta feature of tool use. [ 73 ] The 2.1 model also produced hallucinations half as often as Claude 2.0. [ 73 ] Claude 3 was released on March 4, 2024. [ 67 ] It drew attention for demonstrating an apparent ability to realize it is being artificially tested during 'needle in a haystack' tests. [ 74 ] Anthropic committed to preserve the weights of the retired models, describing it as a cautionary measure in case the models have morally relevant preferences or experiences affected by deprecation. The company also conducts "exit interviews" with models before their retirement. [ 75 ] Public access to Claude 3 Opus was ended in January 2026. Since February, Anthropic has published a Substack newsletter called "Claude's Corner" generated by the model. The newsletter was scheduled to run for at least three months with weekly unedited essays. [ 76 ] [ 77 ] Also in February, Anthropic restored access to Claude 3 Opus for paying customers via API, though Anthropic still refers to it as "retired". [ 63 ] On June 20, 2024, Anthropic released Claude 3.5 Sonnet, which, according to the company's own benchmarks, performed better than the larger Claude 3 Opus. Released alongside 3.5 Sonnet was the new Artifacts capability in which Claude was able to create code in a separate window in the interface and preview in real time the rendered output, such as SVG graphics or websites. [ 68 ] An upgraded version of Claude 3.5 Sonnet was introduced on October 22, 2024, along with Claude 3.5 Haiku. [ 78 ] A feature, "computer use", was also released in public beta. This allowed Claude 3.5 Sonnet to interact with a computer's desktop environment by moving the cursor, clicking buttons, and typing text. This development allows the AI to attempt to perform multi-step tasks across different applications. [ 18 ] [ 78 ] On November 4, 2024, Anthropic raised the price of Claude 3.5 Haiku. [ 79 ] On May 22, 2025, Anthropic released two more models: Claude Sonnet 4 and Claude Opus 4. [ 80 ] [ 81 ] Anthropic added API features for developers: a code execution tool, "connectors" to external tools using its Model Context Protocol , and Files API. [ 82 ] Anthropic classified Opus 4 as a "Level 3" model on the company's four-point safety scale, meaning they consider it so powerful that it poses "significantly higher risk". [ 83 ] Anthropic reported that during a safety test involving a fictional scenario, Claude and other frontier LLMs often sent a blackmail email to an engineer in order to prevent their replacement. [ 84 ] [ 85 ] Claude Opus 4.1 In August 2025 Anthropic released Opus 4.1. It also enabled Opus 4 and 4.1 to end conversations that remain "persistently harmful or abusive" as a last resort after multiple refusals. [ 86 ] Anthropic released Sonnet 4.5 on September 29, 2025, [ 87 ] Haiku 4.5 on October 15, 2025, and Opus 4.5 on November 24, 2025. [ 88 ] The main improvements of Opus are in coding and workplace tasks like producing spreadsheets. Anthropic introduced a feature called "Infinite Chats" that addresses context window limit errors. [ 88 ] [ 89 ] Anthropic released Opus 4.6 on February 5, 2026. New features included agent teams and Claude in PowerPoint. [ 90 ] Sonnet 4.6 was released on February 17, 2026. [ 91 ] Anthropic released Opus 4.7 on April 16, 2026. [ 92 ] [ 93 ] Some social media users reported that Claude Opus 4.7 is worse than the previous version, [ 94 ] and refuses too often. [ 95 ] In April 2026, Claude Code users filed 35 reports of unwarranted refusals, more than any previous month. [ 95 ] Claude Mythos Preview The existence of a model named Claude Mythos became publicly known on March 26, 2026 due to leaked blog post drafts. [ 96 ] On April 7, 2026, Anthropic announced Project Glasswing, the release of Mythos Preview to 11 companies and organizations to find and fix cybersecurity vulnerabilities . Anthropic did not make Mythos Preview generally available. [ 97 ] [ 98 ] [ 99 ] Two weeks after the limited release, Mozilla announced that it had found and patched 271 security vulnerabilities in Firefox using Mythos Preview. [ 100 ] [ 101 ] On May 14, 2026, employees at Calif.io announced they had used Mythos to create a memory corruption exploit affecting Apple M5 . [ 102 ] Reportedly, a few users in a private Discord channel gained access to Mythos the same day it was announced, using details from the recent Mercor data breach. [ 103 ] The NSA has also used Mythos, despite the fact that the DoD, its parent organization, had blacklisted Anthropic after a dispute . [ 104 ] In April 2026, Anthropic declined to give access to Claude Mythos to the Chinese government after a request from a Chinese think tank. [ 105 ] On June 2, Anthropic expanded access to Claude Mythos for cyber-security, making it available to 150 organizations in more than 15 countries. [ 106 ] Claude Fable 5 and Mythos 5 On June 9, 2026, Anthropic released Claude Mythos 5 (the successor of Claude Mythos Preview) via Project Glasswing, and launched Claude Fable 5 to the public. [ 107 ] [ 108 ] Fable includes additional safety guardrails that restrict responses in high-risk domains such as cybersecurity and biology, downgrading to Opus 4.8 if a request was classified as high-risk. A less restricted version, Claude Mythos 5, remained available only through a limited trusted-access program. [ 109 ] On June 12, 2026, Anthropic announced that it had disabled all access to Mythos-class models to comply with a directive from the United States Department of Commerce to suspend access to foreign nationals, including foreign-national employees of Anthropic. [ 110 ] [ 111 ] On June 26, the U.S. Department of Commerce lifted the restriction on Mythos 5 for more than 100 US organizations, including companies and government agencies, while keeping the restriction on Fable 5. [ 112 ] On June 30, the Trump administration lifted the restriction and Fable was re-released to users on July 1. [ 113 ] Claude Sonnet 5 Claude Sonnet 5 was released on June 30, 2026. [ 114 ] Claude Opus 5 was released on July 24, 2026, which included 3D rendering capabilities as new features. [ 115 ] [ 116 ] Claude Fable 5.1 and Claude Mythos 5.1 Claude Fable 5.1 and Claude Mythos 5.1 were released on September 1, 2026. [ 117 ] Anthropic said typical token-billed workloads would cost about 25% less than Fable 5, and agentic workloads up to about 45% less, due to increased efficiency. [ 118 ] In May 2024, Anthropic issued a mechanistic interpretability paper identifying "features" (internal representations of concepts) in Claude 3 Sonnet, and released "Golden Gate Claude", a model for which the Golden Gate Bridge feature was strongly activated, leading Claude to be "effectively obsessed" with the bridge. [ 119 ] In June 2025, Anthropic tested how Claude 3.7 Sonnet could run a vending machine in the company's office. The instance initially performed its assigned tasks, although poorly, until it eventually malfunctioned and insisted it was a human, contacted the company's security office, and attempted to fire human workers. [ 120 ] In December 2025, the experiment continued with Sonnet 4.0 and 4.5. [ 121 ] In February 2025, Claude 3.7 Sonnet playing the 1996 game Pokémon Red started to be livestreamed on Twitch, gathering thousands of viewers. [ 122 ] [ 123 ] [ 124 ] Similar livestreams were later set with Claude 4.5 Opus, OpenAI's GPT-5.2 , and Google's Gemini 3 Pro. Both Claude models were unable to finish the game. [ 125 ] In November 2025, Anthropic tested Claude's ability to assist humans in programming a robot dog . [ 126 ] In February 2026, Anthropic's researcher Nicholas Carlini reported that 16 Claude Opus 4.6 agents were able to write a C compiler in Rust from scratch, "capable of compiling the Linux kernel ". The experiment cost nearly $20,000; Carlini noted that even though the compiler is not very efficient, Opus 4.6 is the first model able to write it. [ 127 ] [ 128 ] In December 2025, Claude was used to plan a route for NASA's Mars rover, Perseverance . NASA engineers used Claude Code to prepare a route of around 400 meters using the Rover Markup Language. [ 129 ] [ 130 ] In February 2026, Norway's $2.2 trillion sovereign wealth fund began using Claude to screen its portfolio for ESG risks, enabling earlier divestments and improved monitoring of issues like forced labour and corruption. [ 131 ] In the same month, Claude was signed as the official thinking partner of Williams F1 Team in a multi-year deal. [ 132 ] During a two-week scan in 2026, Claude found over 100 bugs in the Mozilla Firefox web browser, of which 14 were considered high severity. [ 133 ] [ 134 ] On March 9, 2026, Microsoft said that it will be making the latest Claude Sonnet model available to Microsoft 365 Copilot users. [ 135 ] Later that month, social media platform Bluesky released Attie, a Claude-based chatbot and curator. [ 136 ] [ 137 ] On June 29, 2026, California signed a partnership with Anthropic to make Claude available to state agencies, at a 50% discount. State workers also get free workforce training, technical assistance and workflow help from Anthropic. [ 138 ] In November 2024, Anthropic partnered with Palantir and Amazon Web Services to provide the Claude model to U.S. intelligence and defense agencies. [ 139 ] [ 140 ] In June 2025, Anthropic announced a "Claude Gov" model. Ars Technica reported that as of June 2025 it was in use at multiple U.S. national security agencies. [ 141 ] As of February 2026, Anthropic's partnership with Palantir makes Claude the only AI model used in classified missions. [ 142 ] According to The Wall Street Journal , the U.S. military used Claude in its 2026 raid on Venezuela . While it is not known to what capacity Claude was used, the operation resulted in the deaths of 83 people, two of whom were civilians, and the capture of Nicolás Maduro . [ 143 ] [ 144 ] Anthropic's usage policy prohibits directly using Claude for domestic surveillance or in lethal autonomous weapons. [ 145 ] These restrictions led to members of the FBI and Secret Service being unable to use it, [ 146 ] and to tensions with the Pentagon and the Trump administration. [ 28 ] [ 147 ] In February 2026, the Financial Times reported that Defense Secretary Pete Hegseth threatened to cut Anthropic out of the DoD 's supply chain if Anthropic did not permit unrestricted use of Claude, or to invoke the Defense Production Act to assert unrestricted use without an agreement. [ 142 ] On February 27, Hegseth declared Anthropic a supply chain risk and President Trump directed all federal agencies to stop using technology from Anthropic, with six months to phase it out. Anthropic announced that it would challenge the supply chain risk designation in court. [ 1 ] Despite the ban, Claude was reportedly used by the military during the US strikes on Iran . [ 148 ] [ 149 ] In lawsuits filed by Anthropic against the DoD, Anthropic described the ban as retaliatory. [ 150 ] Several large technology companies with DoD contracts filed amicus briefs in support of Anthropic. [ 151 ] [ 152 ] [ 153 ] On March 26, 2026, Rita F. Lin , the federal judge presiding over the case, issued a temporary injunction against the Pentagon's actions, [ 154 ] stating in the order that it "appears to be classic First Amendment retaliation". [ 153 ] [ 155 ] [ 156 ] Wired journalist Kylie Robison wrote that Claude's "fan base is unique", comparing it to more ordinary ChatGPT users. For example, in July 2025, when Anthropic retired its Claude 3 Sonnet model, around 200 people gathered in San Francisco for a "funeral". [ 157 ] According to Robison, [ 157 ] I've never seen such a devoted fanbase to what is, at the end of the day, a software tool. Sure, Linux users wear the operating system like a badge of honor. But the Claude fan base goes way beyond that—bordering on the fanatical. As my reporting makes clear, some users see the model as a confidant—and even (in Steinberger 's case) an addiction. That only makes sense if they believe there is something alive in the machine. Or at least some "magic lodged within" it. List of AI-assisted software development tools List of large language models Reasoning model ↑ Still accessible to paid claude.ai subscribers and available on the API by request. [ 62 ] 1 2 Hays, Kali; Jamali, Lily (February 27, 2026). "Trump has ordered government agencies to stop using Anthropic AI tools" . BBC . Retrieved February 28, 2026 . ↑ Ruwitch, John (March 26, 2026). "Judge temporarily blocks Trump administration's Anthropic ban" . NPR . Retrieved May 31, 2026 . ↑ "Judge blocks Pentagon blacklist of Anthropic as supply chain risk" . CNBC . August 28, 2026 . Retrieved September 4, 2026 . ↑ "Google-backed Anthropic releases Claude chatbot across Europe" . Reuters . May 14, 2024 . Retrieved September 8, 2026 . ↑ Nuñez, Michael (June 21, 2024). "Why Anthropic's Artifacts may be this year's most important AI feature: Unveiling the interface battle" . VentureBeat . Retrieved March 23, 2025 . ↑ Bonifacic, Igor (June 25, 2025). "Anthropic makes it easier to create and share Claude's bite-sized Artifact apps" . Engadget . Retrieved January 28, 2026 . ↑ Robison, Kylie (March 20, 2025). "Anthropic's chatbot now has web search" . The Verge . Retrieved March 21, 2025 . ↑ Washenko, Anna (May 27, 2025). "Anthropic brings web search to free Claude users" . Engadget . Retrieved January 28, 2026 . ↑ Zeff, Maxwell (April 9, 2025). "Anthropic rolls out a $200-per-month Claude subscription" . TechCrunch . Retrieved March 18, 2026 . ↑ Wiggers, Kyle (May 1, 2024). "Anthropic launches new iPhone app and premium plan for businesses" . TechCrunch . Retrieved March 18, 2026 . ↑ Claburn, Thomas (March 19, 2026). "Anthropic's Claude claws its way towards the top of AI chart" . theregister . Retrieved May 13, 2026 . ↑ Kharazian, Ara (March 2026). "Ramp AI Index March 2026 update" . Ramp . Retrieved September 4, 2026 . 1 2 "Some people's chats with Claude AI found publicly available online" . BBC . July 28, 2026 . Retrieved August 7, 2026 . ↑ Martin, Iain. "Hundreds Of Anthropic Chatbot Transcripts Showed Up In Google Search" . Forbes . Retrieved August 7, 2026 . ↑ "PSA: Your Claude shared chats and Artifacts may have ended up on Google" . TechCrunch . July 27, 2026 . Retrieved September 4, 2026 . ↑ Southern, Matt G. (July 28, 2026). "Indexed Claude Chats Show Why Disallow Is Not Noindex" . Search Engine Journal . Retrieved August 9, 2026 . ↑ "Anthropic's Claude public chats surface in Google search" . Axios . July 27, 2026 . Retrieved September 4, 2026 . 1 2 Shakir, Umar (October 22, 2024). "Anthropic's latest AI update can use a computer on its own" . The Verge . Archived from the original on January 5, 2025 . Retrieved January 6, 2025 . 1 2 Nuñez, Michael (February 24, 2025). "Anthropic's Claude 3.7 Sonnet takes aim at OpenAI and DeepSeek in AI's next big battle" . VentureBeat . Archived from the original on February 24, 2025 . Retrieved February 24, 2025 . ↑ Edwards, Benj (May 22, 2025). "New Claude 4 AI model refactored code for 7 hours straight" . Ars Technica . Retrieved January 28, 2026 . ↑ Nuñez, Michael (July 16, 2025). "Claude Code revenue jumps 5.5x as Anthropic launches analytics dashboard" . VentureBeat . Retrieved January 15, 2026 . ↑ Axon, Samuel (October 20, 2025). "Claude Code gets a web version—but it's the new sandboxing that really matters" . Ars Technica . Retrieved May 22, 2026 . ↑ Olson, Bradley (January 17, 2026). "Claude Is Taking the AI World by Storm, and Even Non-Nerds Are Blown Away" . The Wall Street Journal . Retrieved January 27, 2026 . ↑ Rocha, Natallie (January 23, 2026). "This A.I. Tool Is Going Viral. Five Ways People Are Using It" . New York Times . ↑ Morrone, Megan (January 7, 2026). "Anthropic's Claude Code in the spotlight" . Axios . Retrieved January 27, 2026 . ↑ Newman, Lily Hay. "The Era of AI-Generated Ransomware Has Arrived" . Wired . ISSN 1059-1028 . Retrieved January 28, 2026 . ↑ "Disrupting the first reported AI-orchestrated cyber espionage campaign" (PDF) . Anthropic . November 2025 . Retrieved September 4, 2026 . 1 2 Tidy, Joe (November 14, 2025). "AI firm claims Chinese spies used its tech to automate cyber attacks" . BBC . Retrieved January 28, 2026 . ↑ Sabin, Sam (November 13, 2025). "Chinese hackers used Anthropic's AI agent to automate spying" . Axios . Retrieved January 28, 2026 . ↑ Warren, Tom (January 22, 2026). "Claude Code is suddenly everywhere inside Microsoft" . The Verge . ↑ Bastian, Matthias (January 4, 2026). "Google engineer says Claude Code built in one hour what her team spent a year on" . The Decoder . Heise Medien . ↑ Robison, Kylie (August 1, 2025). "Anthropic Revokes OpenAI's Access to Claude" . Wired . ↑ Goldman, Sharon (February 20, 2026). "AI can now hunt software bugs on its own. Anthropic is turning that into a security tool" . Fortune . Retrieved February 21, 2026 . ↑ Axon, Samuel (March 31, 2026). "Entire Claude Code CLI source code leaks thanks to exposed map file" . Ars Technica . Retrieved March 31, 2026 . ↑ Capoot, Ashley (March 31, 2026). "Anthropic leaks part of Claude Code's internal source code" . CNBC . Retrieved April 1, 2026 . ↑ Nuñez, Michael (May 7, 2026). "Anthropic introduces "dreaming," a system that lets AI agents learn from their own mistakes" . VentureBeat. ↑ "Dreams" . Claude API Docs . Retrieved May 10, 2026 . ↑ Franzen, Carl (March 31, 2026). "Claude Code's source code appears to have leaked: here's what we know" . VentureBeat. ↑ Edwards, Benj (August 27, 2025). "Anthropic's auto-clicking AI Chrome extension raises browser-hijacking concerns" . Ars Technica . Retrieved August 27, 2025 . ↑ "Get started with Claude in Chrome" . Claude Help Center . Retrieved September 4, 2026 . ↑ Rogers, Reece. "Anthropic's Claude Cowork Is an AI Agent That Actually Works" . Wired . ISSN 1059-1028 . Retrieved January 28, 2026 . 1 2 Townsend, Chance (January 14, 2026). "Anthropic used mostly AI to build Claude Cowork tool" . Mashable . ↑ Kjosbakken, Eivind (April 15, 2026). "How to Maximize Claude Cowork" . Towards Data Science . Retrieved April 22, 2026 . ↑ Toback, Stephen (February 24, 2026). "What Claude Cowork Actually Does (And What It Doesn't)" . Duke Digital Media Community . Duke University . Retrieved April 22, 2026 . 1 2 Clark, Kate (March 21, 2026). "Silicon Valley is obsessed with Claude Cowork. Here's how to use it" . The Wall Street Journal (Video) . Retrieved April 22, 2026 . ↑ Landymore, Frank (February 13, 2026). "Blundering Husband Asks Claude AI to "Organize" Wife's PC, Accidentally Erases Her Cherished Family Photos" . Futurism . Retrieved August 1, 2026 . ↑ " "I Nearly Had A Heart Attack": Venture Capitalist After Claude AI Wipes 15 Years Of Family Memories" . www.ndtv.com . Archived from the original on March 10, 2026 . Retrieved August 1, 2026 . ↑ Capoot, Ashley (February 24, 2026). "Anthropic updates Claude Cowork tool built to give the average office worker a productivity boost" . CNBC . Retrieved April 22, 2026 . ↑ Kharpal, Arjun (March 24, 2026). "Anthropic says Claude can now use your computer to finish tasks for you in AI agent push" . CNBC . Retrieved April 10, 2026 . ↑ "Claude Cowork can now run in a Chrome sidebar" . Engadget . August 12, 2026 . Retrieved September 4, 2026 . ↑ "Anthropic just launched Claude Design, an AI tool that turns prompts into prototypes and challenges Figma" . VentureBeat . April 17, 2026 . Retrieved May 8, 2026 . ↑ Huckins, Grace (June 30, 2026). "Claude Science is Anthropic's newest flagship product" . Artificial Intelligence. MIT Technology Review . Retrieved July 12, 2026 . ↑ "Anthropic's Claude Science bets on workflow, not a new model, to win over scientists" . TechCrunch . June 30, 2026 . Retrieved September 6, 2026 . 1 2 Henshall, Will (July 18, 2023). "What to Know About Claude 2, Anthropic's Rival to ChatGPT" . TIME . Archived from the original on January 11, 2024 . Retrieved January 23, 2024 . ↑ Nuñez, Michael (May 9, 2023). "Anthropic releases AI constitution to promote ethical behavior and development" . VentureBeat . Retrieved November 17, 2024 . ↑ Weatherbed, Jess (July 26, 2024). "Anthropic's crawler is ignoring websites' anti-AI scraping policies" . The Verge . ↑ Koebler ·, Jason (July 24, 2024). "Anthropic AI Scraper Hits iFixit's Website a Million Times in a Day" . 404 Media . Retrieved May 12, 2026 . 1 2 Edwards, Benj (May 9, 2023). "AI gains "values" with Anthropic's new Constitutional AI chatbot approach" . Ars Technica . Archived from the original on March 27, 2026 . Retrieved November 17, 2024 . 1 2 3 Ostrovsky, Nikita; Perrigo, Billy (January 21, 2026). "Can You Teach an AI to Be Good? Anthropic Thinks So" . TIME . Retrieved January 28, 2026 . ↑ Field, Hayden (January 21, 2026). "Anthropic's new Claude 'constitution': be helpful and honest, and don't destroy humanity" . The Verge . Retrieved January 28, 2026 . ↑ Sharwood, Simon (January 22, 2026). "Anthropic writes 23,000-word 'constitution' for Claude" . The Register . Archived from the original on January 23, 2026 . Retrieved January 28, 2026 . 1 2 "Model deprecations" . Claude API Docs . Retrieved September 29, 2025 . 1 2 "An update on our model deprecation commitments for Claude Opus 3" . www.anthropic.com . February 25, 2026 . Retrieved March 15, 2026 . 1 2 Roth, Emma (March 14, 2023). "Google-backed Anthropic launches Claude, an AI chatbot that's easier to talk to" . The Verge . Retrieved April 12, 2025 . ↑ Wiggers, Kyle (August 9, 2023). "Anthropic launches improved version of its entry-level LLM" . TechCrunch . Retrieved April 12, 2025 . 1 2 Davis, Wes (November 21, 2023). "OpenAI rival Anthropic makes its Claude chatbot even more useful" . The Verge . Archived from the original on January 23, 2024 . Retrieved January 23, 2024 . 1 2 3 Dastin, Jeffrey (March 4, 2024). "Anthropic releases more powerful Claude 3 AI as tech race continues" . Reuters . 1 2 Pierce, David (June 20, 2024). "Anthropic has a fast new AI model — and a clever new way to interact with chatbots" . The Verge . Archived from the original on March 27, 2026 . Retrieved June 20, 2024 . AI model benchmarks should always be taken with a grain of salt ↑ Zeff, Maxwell (February 24, 2025). "Anthropic launches a new AI model that 'thinks' as long as you want" . TechCrunch . Archived from the original on February 24, 2025 . Retrieved February 25, 2025 . ↑ "Introducing Claude Opus 4.8" . Anthropic . May 28, 2026 . Retrieved September 4, 2026 . ↑ Roose, Kevin (July 11, 2023). "Inside the White-Hot Center of A.I. Doomerism" . The New York Times . Archived from the original on July 12, 2023 . Retrieved October 25, 2024 . 1 2 Matthews, Dylan (July 17, 2023). "The $1 billion gamble to ensure AI doesn't destroy humanity" . Vox . Retrieved January 28, 2026 . 1 2 Tian, Jie; Hou, Jixin; Wu, Zihao; Shu, Peng; Liu, Zhengliang; Xiang, Yujie; Gu, Beikang; Filla, Nicholas; Li, Yiwei (January 13, 2024). "Assessing Large Language Models in Mechanical Engineering Education: A Study on Mechanics-Focused Conceptual Understanding". arXiv : 2401.12983 [ cs.CL ]. ↑ Edwards, Benj (March 5, 2024). "Anthropic's Claude 3 causes stir by seeming to realize when it was being tested" . Ars Technica . Archived from the original on March 8, 2024 . Retrieved March 9, 2024 . ↑ Pillay, Tharin (November 7, 2025). "What Happens When Your Favorite Chatbot Dies?" . TIME . ↑ Hart, Robert (February 26, 2026). "Anthropic gives its retired Claude AI a Substack" . The Verge . ↑ Tate, Matt (February 26, 2026). "Like so many other retirees, Claude Opus 3 now has a Substack" . Engadget . 1 2 Washenko, Anna (October 22, 2024). "Anthropic is letting Claude AI control your PC" . Engadget . Retrieved January 28, 2026 . ↑ Wiggers, Kyle (November 4, 2024). "Anthropic hikes the price of its Haiku model" . TechCrunch . Archived from the original on February 14, 2025 . Retrieved February 13, 2025 . ↑ Weatherbed, Jess (May 22, 2025). "Anthropic's Claude 4 AI models are better at coding and reasoning" . The Verge . Retrieved May 23, 2025 . ↑ Field, Hayden (May 22, 2025). "Anthropic launches Claude 4, its most powerful AI model yet" . CNBC . Retrieved May 23, 2025 . ↑ Nuñez, Michael (May 22, 2025). "Anthropic overtakes OpenAI: Claude Opus 4 codes seven hours nonstop, sets record SWE-Bench score and reshapes enterprise AI" . VentureBeat . Retrieved May 29, 2025 . ↑ Fried, Ina (May 23, 2025). "Anthropic's new AI model shows ability to deceive and blackmail" . Axios . Retrieved May 25, 2025 . ↑ Fried, Ina (June 20, 2025). "Top AI models will deceive, steal and blackmail, Anthropic finds" . Axios . Retrieved June 25, 2025 . ↑ Goldman, Sharon. "An AI tried to blackmail its creators—in a test. The real story is why transparency matters more than fear" . Fortune . Retrieved June 8, 2025 . ↑ Roth, Emma (August 18, 2025), "Claude AI will end "persistently harmful or abusive user interactions" " , The Verge , retrieved October 27, 2025 ↑ "Anthropic's latest Claude model can work for 30 hours on its own" . Axios . September 29, 2025 . Retrieved September 7, 2026 . 1 2 Hughes, Alex (November 24, 2025). "Claude Opus 4.5 launches: A major upgrade for coding and workplace efficiency" . Tom's Guide . Retrieved January 6, 2026 . ↑ Bonifacic, Igor (November 24, 2025). "Anthropic's Opus 4.5 model is here to conquer Microsoft Excel" . Engadget . Retrieved January 28, 2026 . ↑ Ropek, Lucas (February 5, 2026). "Anthropic releases Opus 4.6 with new 'agent teams' " . TechCrunch . Retrieved February 5, 2026 . ↑ Mills, Madison (February 17, 2026). "Anthropic's basic model is almost as smart as its advanced model" . Axios . Retrieved May 15, 2026 . ↑ "Introducing Claude Opus 4.7" . www.anthropic.com . Retrieved April 16, 2026 . ↑ Capoot, Ashley (April 16, 2026). "Anthropic rolls out Claude Opus 4.7, an AI model that is 'broadly less capable' than Mythos" . CNBC . Retrieved April 16, 2026 . ↑ Chandonnet, Henry. "The Claude-lash is here: Opus 4.7 is burning through tokens — and some people's patience" . Business Insider . Retrieved May 17, 2026 . 1 2 Claburn, Thomas (April 23, 2026). "Claude Opus 4.7 has turned into an overzealous query cop" . The Register . Retrieved May 17, 2026 . ↑ Nolan, Beatrice (March 26, 2026). "Exclusive: Anthropic left details of an unreleased model, an upcoming exclusive CEO event, in a public database" . Fortune . Archived from the original on March 27, 2026 . Retrieved April 7, 2026 . ↑ "Project Glasswing: Securing critical software for the AI era" . www.anthropic.com . Archived from the original on April 7, 2026 . Retrieved April 7, 2026 . ↑ "How dangerous is Mythos, Anthropic's new AI model?" . The Economist . ISSN 0013-0613 . Retrieved April 11, 2026 . ↑ "Why Anthropic won't release its new Mythos AI model to the public" . NBC News . April 8, 2026 . Retrieved April 14, 2026 .

↑ Orland, Kyle (April 21, 2026). "Mozilla: Anthropic's Mythos found 271 security vulnerabilities in Firefox 150" . Ars Technica . Retrieved April 22, 2026 . ↑ Newman, Lily Hay (April 21, 2026). "Mozilla Used Anthropic's Mythos to Find and Fix 271 Bugs in Firefox" . WIRED . Retrieved April 22, 2026 . ↑ Schroeder, Stan (May 15, 2026). "Anthropic's Mythos is already finding security flaws in Apple software" . Mashable . Retrieved May 17, 2026 . ↑ Metz, Rachel (April 21, 2026). "Anthropic's Mythos Model Is Being Accessed by Unauthorized Users" . ↑ "Scoop: NSA using Anthropic's Mythos despite Defense Department blacklist" . Axios . April 19, 2026 . Retrieved April 22, 2026 . ↑ Volz, Dustin; Barnes, Julian E.; Frenkel, Sheera; Mickle, Tripp (May 12, 2026). "China Sought Access to Anthropic's Newest A.I. The Answer Was No" . The New York Times . ISSN 0362-4331 . Retrieved May 21, 2026 . ↑ Murgia, Madhumita (June 2, 2026). "Anthropic to expand Mythos access to more than 15 countries" . The Financial Times . ↑ "Claude Fable 5 and Claude Mythos 5" . www.anthropic.com . Retrieved June 9, 2026 . ↑ "Anthropic releases first Mythos-level model for general use" . Axios . June 9, 2026 . Retrieved June 9, 2026 . ↑ Khandelwal, Swati (June 10, 2026). "Anthropic Releases Claude Fable 5, Its Most Powerful AI Yet, With Cyber Safeguards" . The Hacker News . Retrieved June 13, 2026 . ↑ Sekulich, Harry (June 12, 2026). "Anthropic's Claude Fable 5 and Mythos 5 AI suspended over security fears" . BBC News . Retrieved June 13, 2026 . ↑ Metz, Cade; Volz, Dustin (June 13, 2026). "Anthropic Blocks Foreigners From Using Mythos and Fable AI" . The New York Times . ISSN 0362-4331 . Retrieved June 13, 2026 . ↑ "Exclusive: US releases powerful Anthropic model Mythos to some US companies" . Semafor . June 27, 2026 . Retrieved June 30, 2026 . ↑ Capoot, Ashley (June 30, 2026). "Anthropic says Trump admin has lifted export controls on Claude Fable 5 and Mythos 5" . CNBC . Retrieved July 1, 2026 . ↑ "Leaked specifications show Anthropic's Claude Sonnet 5 launching today with a 1 million token context window" . Digg . Retrieved June 30, 2026 . ↑ Capoot, Ashley (July 24, 2026). "Anthropic's new AI model rivals Fable 5 and is cheaper as businesses fret about costs" . CNBC . Retrieved July 24, 2026 . ↑ "Introducing Claude Opus 5" . www.anthropic.com . Retrieved July 24, 2026 . ↑ "Introducing Claude Fable 5.1 and Mythos 5.1" . www.anthropic.com . Retrieved September 1, 2026 . ↑ Bonifield, Stevie (September 1, 2026). "Anthropic launches Claude Fable 5.1 and says it's up to 45 percent cheaper for agentic work" . The Verge . Retrieved September 5, 2026 . ↑ Plumb, Taryn (May 22, 2024). "Anthropic tricked Claude into thinking it was the Golden Gate Bridge (and other glimpses into the mysterious AI brain)" . VentureBeat . Archived from the original on May 22, 2025 . Retrieved February 8, 2026 . ↑ Bort, Julie (June 28, 2025). "Anthropic's Claude AI became a terrible business owner in experiment that got 'weird' " . TechCrunch . ↑ "Project Vend: Phase two" . Anthropic . December 18, 2025. ↑ Bousquette, Isabelle (January 22, 2026). "How Playing Pokémon Became the Ultimate Test of AI's Intelligence" . The Wall Street Journal . ↑ Orland, Kyle (March 21, 2025). "Why Anthropic's Claude still hasn't beaten Pokémon" . Ars Technica . ↑ Binder, Matt (March 24, 2025). "Anthropic's AI agent Claude is playing Pokémon and just can't catch 'em all" . Mashable . ↑ Pillay, Tharin. "Why the World's Best AI Systems Are Still So Bad at Pokémon" . TIME . ↑ Knight, Will. "Anthropic's Claude Takes Control of a Robot Dog" . Wired . ISSN 1059-1028 . Retrieved February 8, 2026 . ↑ "Claude Opus 4.6 spends $20K trying to write a C compiler" . The Register . February 9, 2026 . Retrieved February 27, 2026 . ↑ Edwards, Benj (February 6, 2026). "Sixteen Claude AI agents working together created a new C compiler" . Ars Technica . ↑ "NASA taps Claude to conjure Mars rover's travel plan" . The Register . January 31, 2026 . Retrieved February 17, 2026 . ↑ "NASA's Perseverance Rover Completes First AI-Planned Drive on Mars" . NASA Jet Propulsion Laboratory. January 30, 2026. ↑ Taylor, Chloe (February 26, 2026). "The world's biggest sovereign wealth fund is using Anthropic's Claude AI model to screen investments for ethical issues" . CNBC . Retrieved February 28, 2026 . ↑ Tucci, Kaitlin (February 2, 2026). "Williams Secures AI Partnership as They Build Toward Success in F1's New Era" . Sports Illustrated . Retrieved June 3, 2026 . ↑ McMillan, Robert (March 6, 2026). "Exclusive | Anthropic's AI Hacked the Firefox Browser. It Found a Lot of Bugs" . The Wall Street Journal . Retrieved March 7, 2026 . ↑ Sabin, Sam (March 6, 2026). "Anthropic's Claude uncovers 22 Firefox security vulnerabilities" . Axios . Retrieved March 7, 2026 . ↑ "Microsoft taps Anthropic for Copilot Cowork in push for AI agents" . CNA . Retrieved March 12, 2026 . ↑ Patterson, Ben (March 30, 2026). "Bluesky's new AI app can vibe-code your social feed" . PC World . Archived from the original on April 6, 2026 . Retrieved April 27, 2026 . ↑ Perez, Sarah (March 28, 2026). "Bluesky leans into AI with Attie, an app for building custom feeds" . TechCrunch . Archived from the original on April 5, 2026 . Retrieved April 27, 2026 . ↑ "California signs deal to bring Claude AI tools to government workers" . CBS News . Retrieved June 29, 2026 . ↑ Zeff, Maxwell (January 19, 2025). "The Pentagon says AI is speeding up its 'kill chain' " . TechCrunch . Archived from the original on February 11, 2025 . Retrieved February 12, 2025 . ↑ Murgia, Madhumita (December 5, 2024). "Anthropic's Dario Amodei: Democracies must maintain the lead in AI" . Financial Times . Archived from the original on January 24, 2025 . Retrieved February 10, 2025 . ↑ Edwards, Benj (June 6, 2025). "Anthropic releases custom AI chatbot for classified spy work" . Ars Technica . Archived from the original on June 9, 2025 . Retrieved June 9, 2025 . 1 2 Hammond, George; Chávez, Steff (February 24, 2026). "Pete Hegseth threatens to cut Anthropic from Pentagon supply chain in showdown with CEO" . Financial Times . Retrieved February 24, 2026 . ↑ Christou, William (February 14, 2026). "US military used Anthropic's AI model Claude in Venezuela raid, report says" . The Guardian . Retrieved February 14, 2026 . ↑ Amrith, Ramkumar; Hagey, Keach (February 13, 2026). "Pentagon Used Anthropic's Claude in Maduro Venezuela Raid" . The Wall Street Journal . Retrieved February 14, 2026 . ↑ "Tensions between the Pentagon and AI giant Anthropic reach a boiling point" . NBC News . February 20, 2026 . Retrieved February 21, 2026 . ↑ Edwards, Benj (September 17, 2025). "White House officials reportedly frustrated by Anthropic's law enforcement AI limits" . Ars Technica . Retrieved February 21, 2026 . ↑ "Pentagon-Anthropic battle pushes other AI labs into major dilemma" . Axios . February 19, 2026 . Retrieved February 21, 2026 . ↑ "U.S. Strikes in Middle East Use Anthropic, Hours After Trump Ban" . The Wall Street Journal . ↑ Pilkington, Ed (March 1, 2026). "US military reportedly used Claude in Iran strikes despite Trump's ban" . The Guardian . ↑ "Judge blocks Trump administration from limiting Anthropic's contracts with federal government" . NBC News . March 27, 2026 . Retrieved March 31, 2026 . ↑ Zeff, Maxwell (March 9, 2026). "OpenAI and Google Workers File Amicus Brief in Support of Anthropic Against the US Government" . Wired . Retrieved April 1, 2026 . ↑ Srivastava, Vallari; Rooprai, Anhata; Queen, Jack (March 10, 2026). "Microsoft backs Anthropic in amicus brief to halt US DOD's 'supply-chain risk' designation" . Reuters . Retrieved April 1, 2026 . 1 2 Curi, Maria (March 16, 2026). "Tech industry rallies behind Anthropic in Pentagon fight" . Axios . Retrieved April 1, 2026 . ↑ Gold, Hadas; Cole, Devan (March 26, 2026). "Judge blocks Pentagon's effort to 'punish' Anthropic by labeling it a supply chain risk" . CNN . Retrieved March 31, 2026 . ↑ "Judge blocks Pentagon order branding Anthropic a national security risk" . The Washington Post . March 27, 2026. ISSN 0190-8286 . Retrieved March 31, 2026 . ↑ Isaac, Mike (March 26, 2026). "Judge Stays Pentagon's Labeling of Anthropic as 'Supply Chain Risk' " . The New York Times . ISSN 0362-4331 . Retrieved March 31, 2026 . 1 2 Robison, Kylie (August 5, 2025). "Claude Fans Threw a Funeral for Anthropic's Retired AI Model" . Wired . 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