Hi to ernbo,
Welcome to Adobe Forum,
It will deactivate the CC.
To sign out of the CC desktop App, click on the CC desk cogwheel at the top right hand corner, choose preference, >>accounts>> sign out.
Addition to what Raj said please refer the article: http://helpx.adobe.com/x-productkb/policy-pricing/activation-deactivation-products.html#ho w-to.