Method of providing conditional access to indoor location information in a system comprising a mobile device , a positioning webservice and an authorization authority , the method comprising: - the mobile device performing the steps of: - transmitting license information to the authorization authority and - transmitting a request for indoor location information to the positioning webservice, the request comprising a request-location-estimate corresponding to a location estimate of the mobile device at the time of making the request, - the authorization authority performing the steps of: - receiving the license information, - verifying whether the license information authorizes access to indoor location information by the mobile device , - issuing a secure proof, verifiable by the positioning webservice upon successful verification, the secure proof indicating that the license information authorizes access to indoor location information by the mobile device for an authorized region; - the positioning webservice performing the steps of: - receiving the request for indoor location information and the secure proof; - verifying whether the secure proof authorizes the transmission of indoor location information to the mobile device by verifying, using the secure proof, that the request-location-estimate is within the authorized region; and - upon successful verification sending indoor location information for the request-location-estimate to the mobile device . - the mobile device performing the steps of: - transmitting license information to the authorization authority and - transmitting a request for indoor location information to the positioning webservice, the request comprising a request-location-estimate corresponding to a location estimate of the mobile device at the time of making the request, - transmitting license information to the authorization authority and - transmitting a request for indoor location information to the positioning webservice, the request comprising a request-location-estimate corresponding to a location estimate of the mobile device at the time of making the request, - the authorization authority performing the steps of: - receiving the license information, - verifying whether the license information authorizes access to indoor location information by the mobile device , - issuing a secure proof, verifiable by the positioning webservice upon successful verification, the secure proof indicating that the license information authorizes access to indoor location information by the mobile device for an authorized region; - receiving the license information, - verifying whether the license information authorizes access to indoor location information by the mobile device , - issuing a secure proof, verifiable by the positioning webservice upon successful verification, the secure proof indicating that the license information authorizes access to indoor location information by the mobile device for an authorized region; - the positioning webservice performing the steps of: - receiving the request for indoor location information and the secure proof; - verifying whether the secure proof authorizes the transmission of indoor location information to the mobile device by verifying, using the secure proof, that the request-location-estimate is within the authorized region; and - upon successful verification sending indoor location information for the request-location-estimate to the mobile device . - receiving the request for indoor location information and the secure proof; - verifying whether the secure proof authorizes the transmission of indoor location information to the mobile device by verifying, using the secure proof, that the request-location-estimate is within the authorized region; and - upon successful verification sending indoor location information for the request-location-estimate to the mobile device . <EOS>