# Global Privacy Control (GPC) (/docs/consent-management/concepts/global-privacy-control)

The [Global Privacy Control (GPC)](https://globalprivacycontrol.org/) is a formal [specification](https://privacycg.github.io/gpc-spec/) of the "opt-out preference signal" referenced in the CCPA regulations and CPRA.

The Attorney General of California has declared support for the Global Privacy Control (GPC) signal, and has already [begun enforcing non-compliance](https://oag.ca.gov/news/press-releases/attorney-general-bonta-announces-settlement-sephora-part-ongoing-enforcement) with it.

## Native support [#native-support]

Transcend Consent Management automatically detects the Global Privacy Control signal and opts users out of the sale and sharing of their personal information. Specifically, `airgap.js` will check whether the website visitor has `navigator.globalPrivacyControl` set to `true` in their browser.

When a user has the GPC signal enabled, the consent manager interface will also confirm to the user that their signal has been detected, and they have been automatically opted out.

![Transcend Consent Management, showing the detection of the Global Privacy Control](/images/gpc-consent-banner.png)

## Recommended: Add `gpc.json` to your website [#recommended-add-gpcjson-to-your-website]

To show that your website respects the Global Privacy Control signal, it's [recommended](https://privacycg.github.io/gpc-spec/#gpc-support-representation) to host a [well-known](https://en.wikipedia.org/wiki/Well-known_URI) file on your website. Adding this is completely optional, and has no interaction with Transcend Consent.

At `/.well-known/gpc.json`, respond with:

```json
{
  "gpc": true,
  "lastUpdate": "2021-05-27"
}
```

Set `lastUpdate` to your date of implementation, for versioning purposes.