Anthropic2026-08-15 10:37:18Claude watermark remover nears 9,000 GitHub stars days after Anthropic rolloutAnthropic said on Aug. 11 that Claude-generated text and images will carry hidden watermarks and C2PA digital signatures in response to transparency requirements tied to the European Union’s AI Act. Within three days, a GitHub project called watermarks-remover surged to 8,983 stars, claiming it can strip source markers from Claude, Gemini SynthID, OpenAI outputs, and several open-source watermarking schemes across text and file formats including PNG, PDF, and DOCX. The project, created by developer Guillaume Meyer, was previously named remove-claude-marks and still retains the old command. Its documented approach has three layers: removing invisible Unicode characters, rewriting text to disrupt statistical watermarking, and deleting file signatures and metadata such as C2PA, EXIF, and XMP. But the central issue remains unresolved. Anthropic has not released a public detector for its watermarking system, which means outside researchers, users, and even the tool’s author cannot verify whether Claude’s embedded markers are actually gone. BleepingComputer noted that watermark-removal tools are spreading online, yet almost none can demonstrate that they work. For now, visible metadata may be removable, but claims around statistical watermark removal remain unproven.1930
Anthropic2026-08-13 20:30:24Anthropic starts watermarking Claude text output as developers move to strip the signalAnthropic has started embedding an imperceptible watermark in text generated by its newest Claude models, with the change taking effect for models launched in the European Union on Aug. 2, 2026 and slated to expand globally. The company said the marker applies across every Claude surface, including the chatbot, API, Claude Code, and cloud distribution partners such as Amazon Web Services, Google Cloud, and Microsoft Foundry. Anthropic describes the system as a model-level, text-native watermark that travels with copied text and may survive some editing, while files also receive signed metadata under the C2PA standard. The company has not disclosed the technical method or released public detection tools. That has not stopped outside efforts to remove the marks: GitHub projects already claim to scrub invisible Unicode, rewrite Claude output through other models, and strip C2PA or SynthID-class signals from several file formats. The move is drawing sharper scrutiny because Anthropic previously removed a hidden Claude Code tracker in March after researchers said it marked some users’ location and proxy usage through undisclosed Unicode characters. Anthropic also says the watermark can show Claude touched a text, but not whether the entire piece was written by AI.1760
