What is the rlas3 cookie?
The rlas3 cookie is a third-party identifier used by LiveRamp to resolve browser data into persistent identity envelopes (RampIDs) for cross-site tracking, audience segmentation, and targeted advertising.
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About the rlas3 cookie
| Vendor | LiveRamp |
|---|---|
| Cookie Domain | rlcdn.com |
| Category Category The functional category of the technology, such as Web Analytics or Social Media. Learn more | Advertising & Paid Media |
| Consent Category Consent Category The consent category this cookie most commonly falls under across sites we scan, normalized into four standard categories. Learn more | Targeting & Advertising |
| Prevalence | Very Common |
| Popularity Popularity Popularity is calculated from our dataset of 4.5B+ cookies analyzed across hundreds of millions of web pages. Learn more | Found on 19.2% of scanned pages |
| Expiration Type | Timestamp |
| Expiration Duration | 30 days |
| Party Type Party Type Whether the cookie is first-party or third-party. Learn more | 3rd-Party |
| Risk Level Risk Level Rates how sensitive the data stored by this cookie is (High, Medium, or Low) based on data classification and distribution. Learn more | High |
| Vendor Privacy Policy | https://liveramp.com/privacy/ |
| Vendor Website | https://liveramp.com |
What is the purpose of the rlas3 cookie?
LiveRamp operates an identity resolution and data collaboration platform. The rlcdn.com domain originally belonged to Rapleaf, whose data onboarding division was spun off to form LiveRamp (acquired by Acxiom in 2014, and later established as an independent public company in 2018 after Acxiom spun off its Marketing Services division). The rlas3 cookie serves as LiveRamp's primary third-party identifier, storing a unique LiveRamp cookie ID for a specific browser. It is frequently set when publishers and advertisers embed LiveRamp's Client-Side Tags, Authenticated Traffic Solution (ATS) tags, Real-Time Identity Service pixels, or standard cookie-syncing requests (calling domains such as idsync.rlcdn.com) on their web properties.
When a user visits a participating site, the rlas3 cookie is transmitted in the HTTP request header to LiveRamp's servers. LiveRamp uses this identifier to map the browser to a known user identity (such as a RampID), facilitating cross-device matching, audience segmentation, and targeted advertising. This enables the broader programmatic advertising ecosystem to recognize and address audiences.
What are the Privacy Risks of the rlas3 cookie?
Risk Level: High
The rlas3 cookie is fundamentally designed to enable cross-site tracking, audience profiling, and identity resolution. It powers LiveRamp's ability to sync browser identifiers with persistent offline identities (such as hashed email addresses) and share this data across a vast network of third-party advertising partners and data brokers. Because it facilitates the sharing of pseudonymized but highly deterministic user profiles across the open web, it poses a high privacy risk to end users.
How to Remove the rlas3 cookie from a Website
To stop setting the rlas3 cookie, website administrators must locate and remove any LiveRamp cookie-syncing pixels (often calling idsync.rlcdn.com), Client-Side Tags, or Authenticated Traffic Solution (ATS) tags from their codebase and tag management systems. If LiveRamp is integrated via a third-party advertising or analytics partner, administrators will need to disable cookie syncing for LiveRamp within that partner's platform configuration. It cannot be removed if the site continues to rely on LiveRamp's identity resolution services for unauthenticated traffic.
This definition was last reviewed on August 19, 2026. ObservePoint regularly reviews these definitions to ensure our customers have the most up to date information about the cookies on their websites.