COMPANY PROFILE
Gemius
Headquarters: Warsaw, Poland · Founded: 1999
What it does and how it makes money
Gemius (Gemius S.A., based in Warsaw, Poland) is a research and technology company that measures digital and cross-media audiences for marketers, publishers, media agencies and industry committees in Central and Eastern Europe.
It sells audience-measurement and advertising-effectiveness data and research to publishers, advertisers, agencies and measurement committees. [1]
What data it collects about you
According to its cookie policy, it sets cookies through its clients' websites, links each cookie to the IP address and time of activity, measures ad impressions and clicks and, with consent, uses browsing history for ad targeting. [2]
Fines and sanctions
We found no published fines or sanctions when we checked it on October 12, 2026.
Data breaches and hacks
We found no published data breaches when we checked it on October 12, 2026.
Ask it to delete your data
With GUARDIANA or GUARDIANA ZERO, you download from this same profile the letter asking it to delete your data, under your country’s law, ready to attach to an email.
Its website
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Sources
What this profile does NOT say
- It does not say this company does anything illegal. The only thing it states about anyone’s legality is what a regulator or a court has already decided, with the date and the link to the source.
- It does not say what data of yours it holds: only the company knows, which is why you have the right to ask it.
- If you are this company and a fact is wrong, write to hola@guardianagroup.com and it will be corrected, with its date.
Public facts with their sources, checked on October 12, 2026. All profiles →