What is the tmx_guid cookie?
We don't have a vendor description for this cookie yet, but our scan shows it's set by LexisNexis Risk Solutions (ThreatMetrix), and it typically lasts 13 months. It's listed as unclassified.
Our October 2026 scan found it on 5 sites (0% of the 2,450 we scanned), set before any consent.
- Purpose
- Unclassified
- Belongs to
- LexisNexis Risk Solutions (ThreatMetrix)
- Set as
- First-party on 40% of sites, third-party on 60%
- Typical lifetime
- 13 months
Sites that set tmx_guid before consent
The highest-ranked 5 of 5 sites.
- okx.com0 tracking companies
- philips.com1 tracking company
- chase.com0 tracking companies
- citi.com9 tracking companies
- belkin.com4 tracking companies
Related cookies
Other cookies from LexisNexis Risk Solutions (ThreatMetrix).
- thx_guid5 sites
How to stop it
Declining non-essential cookies in a site's consent banner should stop tmx_guid being set on later visits. Blocking third-party cookies in your browser settings stops the third-party kind everywhere, and clearing cookies for a site removes any it already set.
Understanding this page
- How cookie lifetimes work, and why a 13-month _ga matters
What a cookie's "expires" field actually controls, why Google Analytics ships a 2-year default that many sites cut down to 13 months, and how Safari's 7-day cap on script-set cookies changes the picture.
- First-party vs third-party cookies (and why "first-party" still tracks you)
What the distinction actually means technically, why browsers only block one of the two, and how CNAME cloaking, server-side tagging and cookies like _ga let sites keep tracking under their own domain.
- How to block or limit trackers
Browser privacy settings, content blockers, Global Privacy Control and clearing cookies compared honestly — what each one actually stops, what it doesn't, and what it costs you in return.