Privacy risks and protecting your privacy when accepting cookies

How cookies may harm your privacy

Cookies collect information about your interests, behaviour and preferences. Advertising companies may use this information to compile a profile of you. Advertisers use profiles of people to display targeted advertisements on websites and apps. Advertisers may sell these profiles or share them with other organisations.

The more data companies have about you, the better they can estimate what you want to buy. Advertising companies can also influence you with this information. In this way, the final result of (unconsciously) accepting cookies is that you will be seeing personal advertisements.

Companies may, for example, show you an offer that you may find very attractive, exactly at the right time. Advertisements may persuade you to do certain things or buy certain products, even if you did not intend to do this. As a result, advertisers can have an influence on your choice of products or services. Cookies often play a major role in this.

Examples of privacy risks caused by cookies

Cookies may collect information about relatively harmless subjects. Do you often view, for example, sports gear on apps and websites? Then companies will place you in the category 'sporter'. As a result, you are shown advertisements for sportswear, fitness equipment or sports apps on websites and apps.

Sensitive information

These categories may also be about sensitive subjects. Such as your health, political preference or financial situation. After visiting websites about a certain medical ailment you may, for example, see advertisements for medicines that may cure your ailment.

In addition, cookies can track your political preference. After visiting certain websites, profiles can be created so that you can be divided into groups and shown highly targeted political ads. These political ads canaffect your voting behaviour.

Price influencing

Cookies can also have an influence on the price you pay. Imagine, you want to go on a holiday and look for a flight online. Because cookies track your online behaviour, prices go up each time you visit the website of the company offering the tickets. In this way, the company tries to manipulate you. Because the price keeps going up, you decide at a certain moment to buy the ticket all the same. As a result, you may pay more for the ticket than someone who visits the website of the company for the first time.

Tracking your location

Besides, cookies may track your location through an IP address. This is the unique address of your device (such as a telephone or computer) on the Internet. This enables companies to know where you are. Companies may take advantage of this by, for example, displaying advertisements for local shops and services. Your location can also be tracked and stored over a longer period of time, making it possible to recognise any patterns.

Your data in the hands of other parties

When you accept cookies on a website or an app, your personal data may be shared with hundreds of other companies. There are even websites that share your data with more than a thousand other companies. Often you do not know the identity of these companies. Nor is it always certain if these third parties will use your data safely and responsibly.

After you have accepted cookies, it is almost impossible to know which companies have your data and what they do with them. Besides, you may ask yourself if it is actually necessary that your data are shared with so many other companies.

What you can do to protect your privacy when cookies are used

Adjusting the settings in your browser

You can adjust the privacy settings of many browsers to ensure that you share fewer data with websites that you visit. In some browsers, you can also choose to block some cookies automatically. Do you want to be tracked as little as possible by cookies? How you can arrange this varies for each browser.

• Google Chrome: View the instructions on the website of Google. Under 'Managing your tracking security', Google explains how you can automatically block third-party cookies.
• Safari: View the instructions on the website of Apple for the iPhone, iPad and Mac.
• Microsoft Edge: View the instructions on the website of Microsoft.
• Firefox: View the instructions on the website of Mozilla.

Extensions for your browser

There are several extensions to protect your privacy against cookies. You can find and install extensions through the shop of your browser:

• Google Chrome: Go to the Chrome Web Store.
• Safari: Open the App Store on your Mac, iPad or iPhone and look for extensions for Safari.
• Microsoft Edge: Go to the Microsoft Edge Add-ons page.
• Firefox: Go to the Firefox Add-ons page.

Note: Not all extensions are reliable. Only install extensions of well-known and reliable developers. Do some research, therefore, before you install an extension.

Extensions for cookies

There are extensions that automatically accept or refuse cookies for you. You can indicate this in the settings of the extension. An example of this is the extension Consent-o-Matic. This free extension was made by the University of Aarhus (Denmark). The source code of this extension is publicly available. Everyone can therefore see and check exactly how the extension works.

Tips for making a conscious choice

Read the cookie notification carefully. Take some time to see which cookies the website or app wants to place on your device. And why. You can also read the cookie statement or privacy statement of the website or app. Here you can read how the website or app handles your data. And whether the website or app shares your data with third parties.

Deleting cookies

It is good for your privacy to delete cookies regularly from your device. How you do this varies for each browser.

• Google Chrome: View the instructions on the website of Google.
• Safari: View the instructions on the websites of Apple for iPhone, iPad and Mac.
• Microsoft Edge: View the instructions on the website of Microsoft.
• Firefox: View the instructions on the website of Mozilla.

Are you logged in to some websites by default? After erasing the cookies you will have to log in again.

Automatically erasing cookies

Some browsers can erase your cookies automatically. For example, after one day, or each time you close the browser. You can set this yourself. The instructions for this vary for each browser. We therefore recommend that you take a look at the settings of your browser. Search for terms like 'cookies', 'tracking' or 'browse data' in the settings menu. Extensions that can automatically delete cookies are also available.

Using your privacy rights

Privacy is a fundamental right. That is why you can make a request to advertising companies, websites and apps to gain insight into the data they have about you. And to have these data deleted. You do this through these two privacy rights:

1. Right of access: this right gives you more grip on your personal data. When an organisation processes your personal data, you may ask the organisation what data these are. See the page Right of access for more information.
2. Right to erasure of data: does an organisation not have a good reason (anymore) to process your personal data? Then the organisation will have to delete these data. Note: You cannot always have your personal data deleted. See the page Right to removal of data for more information.