It is a joint project of publishers of the CPEx alliance (Czech Publisher Exchange) and Seznam.cz. The aim is to create a uniform standard for identifying users in online enviroment that is independent of third-party cookies. Czech ad ID system is open to publishers, agencies and advertisers.
The basic data for creating a Czech ad ID is the e-mail address that the user provides to the site operator during registration.
The e-mail address is then converted into an encrypted form in two steps. E.g. The e-mail address uzivatel@priklad.cz can look like this in the coded form: bffa8a26-0a8e-4642-9849-d48288398ba0
This anonymized form of email is then used for the purposes described below.
The Czech ad ID is generated and used only on websites on which the user is registered and logged in, and to which he has given informed consent.
The website operator processes the user’s e-mail, which the user provides during registration / logging in.
CPEx and Seznam process the hashed form of the e-mail and the Czech ad ID itself (i.e. an encoded and anonymized identifier) using the Czech ad ID system.
The legal basis for data processing is the user’s consent.
The user’s e-mail is stored in the website operator’s registration database.
Encoded versions of the e-mail are stored on the servers of the Czech ad ID service. In some cases, the Czech ad ID can be stored on the page:
• in the cookie named “czaid”,
• in local storage under the key “czaid”.
Creation/gathering of a common technical medium similar to a network identifier for singling out and re-recognizing a registered user without being directly identified. This identifier can then be used to:
• Advertising targeting based on website browsing history, e.g.:
• targeting thematic audiences (e.g. interest in fashion, interest in technology, etc.),
• retargeting etc.
• Technical delivery and measurement of advertising (frequency capping, measurement of advertising impressions, measurement of conversions, etc.).
• Content targeting based on website browsing history.
• Web analytics and reporting (visitor measurement, browsing history, etc.).
• Product development and improvement.
We never share the email itself in its original readable form (e.g. uzivatel@priklad.cz) with third parties.
Primary or Secondary ID (i.e. anonymized email in encrypted form) may be shared with:
• Media houses, publishing houses and agencies that are involved in the system:
• Mafra a.s.
• Czech News Center a.s.
• Economia a.s.
• Vltava Labe Media a.s.
• Seznam.cz, a.s.
• Systems for the automated sale and/or purchase of advertising (eg Magnite, Pubmatic, Adform, Sklik etc.).
• Audience management and distribution systems (eg Adobe Audience Manager, Adform, Piano, etc.).
• The user’s email in its original form (e.g. uzivatel@priklad.cz) is never shared with third parties.
• Email is anonymized in two stages:
o Primary ID:
Email is encrypted with a one-way SHA-256 hashing algorithm. The output is a set of characters from which the original e-mail cannot be deciphered (2256 attempts would be needed for a brute-force attack). The resulting character set is only used internally and is not shared with third parties.
o Secondary ID:
Subsequently, a random ID in UUID4 format is assigned to the given hash, which is changed regularly. Only this ID is then shared with third parties.
• The API for the Czech ad ID service is not public, i.e. Anyone can request to generate a Czech ad ID, but only an authorized partner who meets the conditions for using the service.
• Czech ad ID is created with a limited lifetime and after its expiration a new one must be generated.
• The service’s database is stored on a secure cloud storage in EU states that meets DIN ISO/IEC 27001 certification.
• All servers used are in a closed local network. Access from the outside is protected by a firewall that allows only 2 types of connections:
o HTTPS or HTTP connections, where this communication is only allowed on the servers that host the REST API,
o SSH but only via the edge node.
• All other connections are blocked by the firewall and the aforementioned ports are only available for dedicated servers. Data servers are accessible only within the local network and access from outside is blocked. Access to the data servers is also protected by a password.
We only use so-called technical cookies on the Czechadid.cz website. That is, cookies that are really necessary for their operation. The creation and storage of these cookies in the end device does not require the consent of the actual users, specifically in the sense of the provisions of § 89 paragraph 3 of Act No. 127/2005 Coll., on electronic communications and on the amendment of some related laws (Electronic Communications Act) From this reason, we are not giving an option to comment on the creation and storage of cookies on our website.
On our website, you will encounter a maximum of the following technical cookies:
| cookie name | processor | purpose |
| pll_language / wp_lang | czechadid.cz | verification of the language in the users browser |
| wordpress_test_cookie | czechadid.cz | verification if the cookies in the browser are enabled for the smooth run of the website |