Management of cookies

When you consult a website published by a CNRS entity, information may be recorded in 'cookie' files placed on your computer, tablet or mobile phone. This page gives details of what a cookie is, what it is used for and how you can enable or refuse cookies that are not essential for the site to function or for its management.

What is a cookie?

A cookie is a small text file containing small quantities of information. These can include an identifier in the form of a number, a session for example, a choice of language, a code that protects your browsing activity, the name of the server that placed the cookie there and possibly an expiry date. Subject to your choices for cookies that are not necessary for the site to function, generally cookies are stored temporarily on the hard disk of your computer, tablet or mobile (your terminal) when consult a website via your browser. Your web browser manages cookies which users can read by right-clicking on the web page concerns and selecting 'Inspect code'.

Only the sender of a cookie is likely to modify the information it contains. These are either session or permanent/persistent cookies.

A session cookie only lasts during the browsing session before being deleted when you close your browser. A permanent cookie is installed for a specific period of time. In fact this type of cookie remains on the terminal until it expires or is deleted from the computer through the browser settings or extensions.

A cookie only identifies terminal's browser and not you personally. Some cookies need your prior consent before they can be installed on your terminal.

What are cookies used for?

Required cookies

These cookies are placed exclusively by the site editor and are essential for browsing the site. They cannot be deactivated or configured and doing so may affect your ability to access the site or its services and/or the display of these. They enable you to use the site's main features and also secure your connection. Your prior consent is not required for these cookies to be placed. Generally their lifetime does not exceed the duration of the session.

Functional cookies

These cookies are necessary for the site to function. Your prior consent is not required for these cookies to be placed. These cookies enable:

  • Anonymous statistics on visits to and use of the various components of the site to be compiled. These enable the site publisher to administer and enhance the site.
  • The presentation of the site to be adapted to your terminal's display preferences (language used, display resolution, operating system used, etc.) during your visits to the site. This of course depends on your terminal's hardware and the viewing or reading software installed.

Sites published by CNRS entities use the Matomo web analytics tool which complies with GDPR specifications and provides information on site visits, etc. The Matomo tool may deposit several cookies with a lifespan ranging from the session time to 10-30 minutes and up to 11 months.

Functional cookies placed by the CNRS:

  • Name: _pk_ses
    Service provided: Visitor statistics (Matomo)
    Purpose: This cookie temporarily stores the current session
    Duration: 30 minutes

  • Name: _pk_id
    Service provided: Visitor statistics (Matomo)
    Purpose: This cookie assigns a unique identifier to the user
    Duration: 11 months

  • Name: _pk_testcookie
    Service provided: Site traffic statistics (Matomo)
    Purpose: This cookie verifies whether the browser accepts cookies
    Duration: Session

    Service provided: CSRF (cross-site request forgery) protection
    Purpose: Prevents fraud, protects users and the reliability of data collected by Matomo
    Duration: Session

Third-party cookies:

Some sites may include third-party software applications which place 'social', advertising, targeting and tracking cookies.

This particularly involves services covering:

  • Consent or refusal to deposit cookies from the Axeptio tool, published by the French company Agilitation which the CNRS choose for cookie management.
  • Viewing video content hosted on YouTube, Dailymotion, etc.
  • Sharing information on social networks that enables you to share content with other people on the site or to inform such people that you consulted content on our site or your opinion thereon.

The third-party cookies may record the pages and websites you visit and collect personal data like your IP address which they then share with third parties. These cookies enable advertisers to send you targeted and personalised advertising. The cookies have variable lifespans ranging from session duration or a few dozen minutes to several years.

The CNRS site that you visit has no control over the process(es) used by content hosts and social networks to collect information related to your browsing and associated with any personal data they may possess.

It is possible for you to manage the placement of these cookies. However you first need to accept such third-party cookies before you can view certain content offered by the CNRS.

How to manage cookies on this CNRS site

The prior consent of users is required for cookies whose sole purpose is not to enable or facilitate electronic communication or which are not strictly necessary to provide an online communication service expressly requested by those users.

Tracers that solely measure the site or application's anonymous audience for operational purposes and for the day-to-day administration of a website are not subject to consent.

You have several complementary options to manage cookies deposited by a CNRS site. You may:

  • Accept or refuse unnecessary or non-functional cookies with the Axeptio certified consent tool provided or used on most CNRS sites. On such sites concerned there is a 'Cookie management' widget button that enables you to accept or refuse cookies requiring your consent, particularly third-party cookies. The widget gives information on the purposes of these cookies and a link to their privacy protection policy via a "?
  • Make choices as regards third-party companies by consulting their privacy protection policies. These give the purposes of use, in particular for advertising, and details of the browsing information they may collect thanks to the application buttons available on the site consulted. You can also configure your user accounts to accept or refuse the tracers these companies deposit.
  • Control cookies using your browser settings. Most of these tracers can be deactivated in the preference settings of your browser so it only accepts tracers from sites visited (refuse 'third party sites', tick the 'Do not track me' box on most browsers). In 'Private Browsing' mode, cookies will only disappear when you close your browser window.

How to configure your browser

To manage cookies as best you wish, we invite you to configure your browser depending on the purpose of the cookies:

  • Internet browsers can be configured to send you an alert before a cookie is installed.
  • Your browser can also be set to refuse all types of cookies or third-party cookies alone.
  • Any cookies already installed on the computer can be deleted.
  • Each browser you use needs to be configured separately to refuse cookies.

Deactivating/deleting cookies on your browser

For Internet Explorer™:

For Safari™:

For Safari™mobile:

For Chrome™:

For Firefox™:

For Opera™:

For Microsoft Edge™:

You can use cookie and other tracker blockers via extensions on your browser such as:

Please note

Blocking required or functional cookies can disrupt your browsing and restrict the services offered.

To manage advertising cookies for certain advertisers on two professional platforms and on Google:

To deactivate social network cookies

Smartphone settings

For iOS™:

For Android™:

For further information on managing cookies on other browsers, please consult the corresponding documentation or online help files.

The CNIL website also gives information on how to configure your browser to control the placement of cookies on your computer, tablet or smartphone.

The CNRS Data Protection Officer

For any questions about the CNRS's cookie management policy, please contact the CNRS Data Protection Officer.

Contact the Data Protection Office