Aus belanglosen Daten können Persönlichkeitsprofile entstehen




Personality profiles can emerge from seemingly irrelevant data




Tracking programmes alert third parties when you click on a link, interact with an advertisement, watch a video, etc. These isolated pieces of information may not mean much on their own, but the sum total can allow conclusions to be drawn on significant aspects of your personality.  

How is someone tracked?

Today, tracking technologies are widespread both on the internet and in the analogue world. 

Web tracking uses various technologies that focus on various forms of data in order to track user behaviour and that are constantly evolving. In simple terms, web tracking combines factual information (e.g. you have clicked on a link) with certain characteristics or features in order to clearly associate a certain behaviour with an end device or a person. 

Examples of web tracking methods:

  • websites place cookies or other files in the visitor's browser, which collect information about surfing behaviour and can replay this information when it is requested;
  • the links in an email or on a web page are either unique or personalised in such a way that the server can trace their use;
  • web pages or applications convert all displayed links into its own links in order to register on their own server when visitors click on external links;
  • graphics embedded in web pages or e-mails make it possible to determine whether the page or e-mail has been opened. Some of these graphics are visible (e.g. social plugins, embedded videos, etc.); others are invisible (e.g. tracking pixels or web beacons). 

Tracking is carried out on the internet primarily to optimise website analyses, i.e. so as to evaluate the performance of internet pages, and to support online advertising and marketing campaigns

Companies that specialise in behavioural marketing and advertising collect data about people's surfing behaviour in order to generate more suitable advertisements and product suggestions. The logic is that the more data that is available about users, the better the algorithms predict their preferences. Therefore, the information on surfing behaviour is often supplemented with information from other sources (e.g. social media or other websites visited) or with predictions or information calculated by algorithms, which can create user profiles (profiling). 


The behaviour and movements of people can also be tracked in analogue space and in different ways, including using intelligent cameras that recognise faces or other features, or capture the number plates of passing vehicles.

Tracking can also be done by recognising objects that people carry in the different places they visit. These objects include RFID chips in labels, cards, library books, etc., which emit radio waves and can thus be detected by a reader, and mobile devices such as mobile phones, which emit signals to connect to an antenna, a WLAN or via Bluetooth. These tracking technologies are constantly evolving.


When is tracking relevant under data protection law?

In terms of data protection law, tracking becomes the processing of personal data if the data that is collected and evaluated can be related to an identified or identifiable person. If this is the case, then these data processing operations are subject to the data protection provisions.

The relation to a person arises not only when the data itself has an identifying characteristic (e.g. the unique user identifier UID for Android or Ad-ID for Apple devices), but can also arise depending on the circumstances of collection and evaluation, for example if the data is stored for a long time, linked with others, or if it is very specific. Even if data is to be processed anonymously, it must be assumed that it is personal data until it has been completely anonymised, so that the data protection requirements are complied with. 

Is tracking people allowed?

The legality of tracking people depends on the specific circumstances of the individual case, since tracking can be carried out in different ways and for various purposes. As in many cases the data that are used for tracking were originally generated for technical reasons, tracking may breach the principle that data should only be used for the originally stated purpose (the ‘purpose limitation principle’) . Tracking may also breach the principles that processing should be proportionate (Art. 6 para. 2 FADP) and that the minimum amount of data should be used (Art. 7 para. 3 FADP). Accordingly, tracking people is generally only permissible if it is justified by an overriding interest or if the data subject consents to it. 

for those responsible


Only collect data that you actually need and delete it immediately, as soon as you no longer need it.


Carefully read the terms of use of the tools you use. They often contain a clause that permits the provider to use the data that you collect for its own purposes. Disclosing data to third parties in this way is not permitted without justification or permission.


Design your website so that visitors can decide for themselves whether they want to be tracked.  


Find out about privacy-friendly tools and settings that allow you to measure the performance of a website or newsletter while respecting the privacy of your visitors. 


Instead of using trackers on your website or emails, you can manually use generic UTM parameters in links. For example, you can add «?utm_source=email» to the links in your newsletters. This will allow you to see in your analytics platform how many users have come to a page via that link.


Instead of relying on data, you can personalise advertising based on content. 


Remember that the data you collect can be misused. What is completely harmless to someone in one context can be used to hurt and harm that person in another context.

for people whose data is processed (data subjects)


Find out about your rights and check how websites and apps handle your data.


Give preference to search engines, social media and websites that value your privacy.


Use privacy enhancer plugins and browsers that help protect you from tracking. 


Further topics

Right to be forgotten on the internet

Search engines make information that was published on the internet at a certain point in time accessible to everyone... including information that one would sometimes rather forget.

Advertising & marketing

Mail, e-mail, telephone: Depending on the type of contact, different rules apply for data protection-compliant advertising.

Data processing in the cloud

More and more businesses and public authorities are using cloud services and outsourcing their data or data processing tasks to a cloud service provider

Privacy statements on the internet

Who needs a privacy statement and what should it contain?

Questions on data protection

Take a look at our FAQ or call our hotline.


Here you can download all documents sorted by topics.

The main provisions

Here you can find out more about changes to the Data Protection Act, which came into force on 1 September 2023.

Last modification 19.04.2023

Top of page