Data addendum for "Widespread Third-Party Tracking On Hospital Websites"

For each hospital web page, we only recorded data requests that initiated data transfers to third-party domains. We then used the webXray database to determine the corporation associated with the third-party domain and the majority owner of the corporation (i.e., the “parent company”) at the time the study occurred (August 2021). For example, the corporation associated with the third-party domain doubleclick.net was determined to be Google, which is majority owned by Alphabet. <br> Our research does not indicate that the corporations or parent companies listed in our report received data from hospital website browsing; rather, the parent companies listed owned a corporation affiliated with the third-party domains initiating these data requests. We observed only data transfers from the browser to the domain; we did not observe the subsequent use of the data. We do not claim that any third-party domain listed was requesting or receiving this data in a manner that violated applicable laws or regulations governing consumer data privacy. <br> Below is a table that lists each parent company and the listed domains associated with a corporation owned by such parent company.