Chrome is Silently Installing a 4GB AI Model on Your PC—And It Will Restore It If You Remove It

Check your Chrome data folder. There’s a good chance that the 4GB AI version is sitting there – which you didn’t agree to install. The file is called weights.bin, placed in a folder called OptGuideOnDeviceModel. It’s a lightweight version of Gemini Nano, Google’s language version for devices.

Remove it and Chrome will reload.

Private investigator Alexander Hanff research this behavior when you run the search automatically on a new Chrome profile. Using the macOS kernel file logs, they tracked Chrome and created a temporary directory, downloaded the prototype components, and put the finished file on disk. The whole process took about 15 minutes. No clue. There is no rush. The profile received zero human input at any time.

The same method has been confirmed for Windows 11, Apple Silicon Macs, and Ubuntu. Users who have been accessing anonymous storage for a year now have the name of the culprit.

What it does

Gemini Nano powers Chrome’s AI features on devices: Features like “Help me write email,” fraud detection, smart paste, page summaries, and AI-powered categories. On Windows, the file is located at %LOCALAPPDATA%\Google\Chrome\User Data\OptGuideOnDeviceModel\weights.bin. On Mac and Linux, it’s the same Chrome folder.

Deleting the directory does not provide permanent relief. Chrome restores it at the next restart only if you disable the feature-through the chrome: // flag, switch on Device AI in Settings > System, or on Windows, switch OptimizationGuideModelDownloading to disabled.

Chrome recently added the popular “AI Mode” button to the bar. A casual user seeing the button – with a standard 4GB version already on their disk – might think that their questions remain on the device. They don’t. AI Mode sends every query to Google’s cloud servers. The local version of the Gemini Nano does not provide any power at all.

You’re paying for storage and bandwidth for something you’re not using privately.

Is it legal or “legal”?

Hanff says Google is violating EU privacy laws. His case is pending Article 5(3) of the ePrivacy Directive-the same paragraph behind the cookie consent notices – which require “acceptance, free provision, authentication, notification, and clarity” before storing anything on the user’s device. They also refer to GDPR Articles 5(1) and 25, which address transparency and privacy in the process.

He also made a specific reference to a case he had published two weeks earlier: Anthropic’s Claude Desktop was quietly installed on nearly three million users’ machines without permission. It’s the same example, he argued, but on a much smaller scale.

However, Google has been sneaking Gemini Nano into Chrome for a while. People didn’t notice. “To give you the best browsing experience, Chrome uses on-device AI models to improve the web and browser experience,” Google says in a statement. Help Page. “Chrome can download Generative AI background tools, so tools that depend on these device models are ready to use. If you remove AI models from a device, those dependencies will not be available.”

“In February, we started giving users the ability to disable and uninstall the version directly from Chrome’s settings. Once disabled, the version will not be downloaded or updated again.” the company he said Android Authority.

The company noted that the brand automatically deletes itself if the storage is running low. What Google didn’t answer was why users weren’t asked first.

Its about Google Chrome design documentation it tells third-party developers “it’s the best way to let the user know how long it takes to download.” Google did not follow its instructions this time.