{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,8]],"date-time":"2026-02-08T19:30:20Z","timestamp":1770579020708,"version":"3.49.0"},"reference-count":46,"publisher":"Association for Computing Machinery (ACM)","issue":"4","license":[{"start":{"date-parts":[[2018,8,7]],"date-time":"2018-08-07T00:00:00Z","timestamp":1533600000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/www.acm.org\/publications\/policies\/copyright_policy#Background"}],"funder":[{"DOI":"10.13039\/501100000266","name":"UK Engineering and Physical Sciences Research Council","doi-asserted-by":"crossref","award":["EP\/J017728\/2"],"award-info":[{"award-number":["EP\/J017728\/2"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"crossref"}]}],"content-domain":{"domain":["dl.acm.org"],"crossmark-restriction":true},"short-container-title":["ACM Trans. Internet Technol."],"published-print":{"date-parts":[[2018,11,30]]},"abstract":"<jats:p>Third-party networks collect vast amounts of data about users via websites and mobile applications. Consolidations among tracker companies can significantly increase their individual tracking capabilities, prompting scrutiny by competition regulators. Traditional measures of market share, based on revenue or sales, fail to represent the tracking capability of a tracker, especially if it spans both web and mobile. This article proposes a new approach to measure the concentration of tracking capability, based on the reach of a tracker on popular websites and apps. Our results reveal that tracker prominence and parent\u2013subsidiary relationships have significant impact on accurately measuring concentration.<\/jats:p>","DOI":"10.1145\/3176246","type":"journal-article","created":{"date-parts":[[2018,8,8]],"date-time":"2018-08-08T19:14:21Z","timestamp":1533755661000},"page":"1-22","update-policy":"https:\/\/doi.org\/10.1145\/crossmark-policy","source":"Crossref","is-referenced-by-count":37,"title":["Measuring Third-party Tracker Power across Web and Mobile"],"prefix":"10.1145","volume":"18","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4718-2190","authenticated-orcid":false,"given":"Reuben","family":"Binns","sequence":"first","affiliation":[{"name":"University of Oxford, Department of Computer Science, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Zhao","sequence":"additional","affiliation":[{"name":"University of Oxford, Department of Computer Science, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Max Van","family":"Kleek","sequence":"additional","affiliation":[{"name":"University of Oxford, Department of Computer Science, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nigel","family":"Shadbolt","sequence":"additional","affiliation":[{"name":"University of Oxford, Department of Computer Science, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"320","published-online":{"date-parts":[[2018,8,7]]},"reference":[{"key":"e_1_2_1_1_1","doi-asserted-by":"publisher","DOI":"10.1145\/2508859.2516674"},{"key":"e_1_2_1_2_1","doi-asserted-by":"publisher","DOI":"10.1257\/jel.54.2.442"},{"key":"e_1_2_1_3_1","unstructured":"Jonathan Anderson Joseph Bonneau and Frank Stajano. 2010. Inglorious installers: Security in the application marketplace. In WEIS. Citeseer.  Jonathan Anderson Joseph Bonneau and Frank Stajano. 2010. Inglorious installers: Security in the application marketplace. In WEIS. Citeseer."},{"key":"e_1_2_1_4_1","unstructured":"Julia Angwin. 2016. Google has quietly dropped ban on personally identifiable web tracking. ProPublica. https:\/\/www.propublica.org.  Julia Angwin. 2016. Google has quietly dropped ban on personally identifiable web tracking. ProPublica. https:\/\/www.propublica.org."},{"key":"e_1_2_1_5_1","doi-asserted-by":"publisher","DOI":"10.1145\/2666356.2594299"},{"key":"e_1_2_1_7_1","volume-title":"WhatsApp is going to share your phone number with Facebook","author":"Bailey Brandon"},{"key":"e_1_2_1_8_1","doi-asserted-by":"publisher","DOI":"10.1109\/MALWARE.2011.6112328"},{"key":"e_1_2_1_9_1","unstructured":"Ben Bold. 2017. Google and facebook dominate over half of digital media market. Retrieved from https:\/\/www.campaignlive.co.uk\/article\/google-facebook-dominate-half-digital-media-market\/1444793.  Ben Bold. 2017. Google and facebook dominate over half of digital media market. Retrieved from https:\/\/www.campaignlive.co.uk\/article\/google-facebook-dominate-half-digital-media-market\/1444793."},{"key":"e_1_2_1_10_1","volume-title":"Wallach","author":"Book Theodore","year":"2015"},{"key":"e_1_2_1_11_1","volume-title":"Proceedings of the 13th Workshop on Economics of Information Security.","author":"Clayton Richard","year":"2014"},{"key":"e_1_2_1_12_1","first-page":"2014","article-title":"U.S. takes the gold in doling out privacy fines","volume":"17","author":"Cline Jay","year":"2014","journal-title":"Computerworld"},{"key":"e_1_2_1_13_1","unstructured":"James Covert. 2016. Twitter kicked tires on yahoo merger. Retrieved from http:\/\/nypost.com\/2016\/06\/02\/twitter-talks-to-yahoo-about-merger\/.  James Covert. 2016. Twitter kicked tires on yahoo merger. Retrieved from http:\/\/nypost.com\/2016\/06\/02\/twitter-talks-to-yahoo-about-merger\/."},{"key":"e_1_2_1_14_1","doi-asserted-by":"publisher","DOI":"10.1093\/joclec\/nhv016"},{"key":"e_1_2_1_15_1","first-page":"2","article-title":"Android and competition law: Exploring and assessing google\u2019s practices in mobile. Euro","volume":"12","author":"Edelman Benjamin G.","year":"2016","journal-title":"Competit. J."},{"key":"e_1_2_1_16_1","volume-title":"Proceedings of the Network and Distributed System Security Symposium (NDSS\u201911)","author":"Egele Manuel","year":"2011"},{"key":"e_1_2_1_17_1","doi-asserted-by":"publisher","DOI":"10.1145\/2619091"},{"key":"e_1_2_1_18_1","doi-asserted-by":"publisher","DOI":"10.1145\/2976749.2978313"},{"key":"e_1_2_1_19_1","doi-asserted-by":"publisher","DOI":"10.1145\/2736277.2741679"},{"key":"e_1_2_1_20_1","volume-title":"Variations in tracking in relation to geographic location. arXiv Preprint arXiv:1506.04103","author":"Fruchter Nathaniel","year":"2015"},{"key":"e_1_2_1_21_1","unstructured":"Commissioner Pamela Jones Harbour. 2007. Dissenting Statement in the Matter of Google\/Doubleclick. FTC File No. 071-0170. (2007).  Commissioner Pamela Jones Harbour. 2007. Dissenting Statement in the Matter of Google\/Doubleclick. FTC File No. 071-0170. (2007)."},{"key":"e_1_2_1_22_1","first-page":"2014","article-title":"Privacy and competitiveness in the age of big data","volume":"26","author":"Hustinx P.","year":"2014","journal-title":"European Data Protection Supervisor"},{"key":"e_1_2_1_23_1","volume-title":"Revenue Report","author":"IAB.","year":"2015"},{"key":"e_1_2_1_24_1","volume-title":"The microsoft-yahoo merger: Yes, privacy is an antitrust concern","author":"Lande Robert H.","year":"2008"},{"key":"e_1_2_1_25_1","doi-asserted-by":"crossref","unstructured":"Christophe Leung Jingjing Ren David Choffnes and Christo Wilson. 2016. Should you use the app for that? Comparing the privacy implications of app-and web-based online services. (unpublished).  Christophe Leung Jingjing Ren David Choffnes and Christo Wilson. 2016. Should you use the app for that? Comparing the privacy implications of app-and web-based online services. (unpublished).","DOI":"10.1145\/2987443.2987456"},{"key":"e_1_2_1_26_1","first-page":"3544","article-title":"Exposing the invisible web: An analysis of third-party HTTP requests on 1 million websites","volume":"9","author":"Libert Timothy","year":"2015","journal-title":"Int. J. Commun."},{"key":"e_1_2_1_27_1","volume-title":"Proceedings of the Symposium on Usable Privacy and Security (SOUPS\u201914)","author":"Lin Jialiu"},{"key":"e_1_2_1_28_1","doi-asserted-by":"publisher","DOI":"10.1145\/2889160.2889178"},{"key":"e_1_2_1_29_1","volume-title":"Erfolgreicher Anzeigenverkauf in Mobilen Medien: Eine Empirische Analyse Zu Verkaufsindikatoren im Mobile Advertising","author":"Meier Saskia"},{"key":"e_1_2_1_30_1","volume-title":"Valletti","author":"Montes Rodrigo","year":"2015"},{"key":"e_1_2_1_31_1","volume-title":"Data-Driven Innovation: Big Data for Growth and Well-Being","author":"Organisation"},{"key":"e_1_2_1_32_1","doi-asserted-by":"publisher","DOI":"10.14722\/ndss.2014.23270"},{"key":"e_1_2_1_33_1","first-page":"1009","article-title":"Privacy, antitrust, and power","volume":"20","author":"Pasquale Frank A.","year":"2013","journal-title":"George Mason Law Rev."},{"key":"e_1_2_1_34_1","doi-asserted-by":"publisher","DOI":"10.1109\/ICC.2015.7249466"},{"key":"e_1_2_1_35_1","doi-asserted-by":"publisher","DOI":"10.1145\/2938559.2938563"},{"key":"e_1_2_1_36_1","doi-asserted-by":"publisher","DOI":"10.5555\/2228298.2228315"},{"key":"e_1_2_1_37_1","unstructured":"Sam Schechner. 2017a. Germany says facebook abuses market dominance to collect data. Retrieved from https:\/\/www.wsj.com\/articles\/facebook-abuses-its-dominance-to-harvest-your-data-says-german-antitrust-enforcer-1513680355.  Sam Schechner. 2017a. Germany says facebook abuses market dominance to collect data. Retrieved from https:\/\/www.wsj.com\/articles\/facebook-abuses-its-dominance-to-harvest-your-data-says-german-antitrust-enforcer-1513680355."},{"key":"e_1_2_1_38_1","unstructured":"Sam Schechner. 2017b. In-app mobile ad spend to reach 45.3bn facebook and google rejoice. Retrieved from http:\/\/adage.com\/article\/digital\/facebook-google-dominate-45-billion-app-ad-market\/310761\/.  Sam Schechner. 2017b. In-app mobile ad spend to reach 45.3bn facebook and google rejoice. Retrieved from http:\/\/adage.com\/article\/digital\/facebook-google-dominate-45-billion-app-ad-market\/310761\/."},{"key":"e_1_2_1_39_1","first-page":"49","article-title":"The 2010 horizontal merger guidelines: From hedgehog to fox in forty years","volume":"77","author":"Shapiro Carl","year":"2010","journal-title":"Antitrust Law J."},{"key":"e_1_2_1_40_1","first-page":"7","article-title":"Protecting consumers: Privacy matters in antitrust analysis","volume":"19","author":"Swire Peter","year":"2007","journal-title":"Cent. Am. Prog."},{"key":"e_1_2_1_41_1","doi-asserted-by":"publisher","DOI":"10.1145\/3052973.3052990"},{"key":"e_1_2_1_42_1","volume-title":"Tracking the trackers: Towards understanding the mobile advertising and tracking ecosystem. arXiv Preprint arXiv:1609.07190","author":"Vallina-Rodriguez Narseo","year":"2016"},{"key":"e_1_2_1_43_1","doi-asserted-by":"publisher","DOI":"10.1145\/3025453.3025556"},{"key":"e_1_2_1_44_1","volume-title":"Comments Prepared for the FTC and US DOJ Merger Enforcement Workshop.","author":"Verouden Vincent","year":"2004"},{"key":"e_1_2_1_45_1","unstructured":"Frederick R. Warren-Boulton. 1990. Implications of US experience with horizontal mergers and takeovers for canadian competition policy. The Law and Economics of Competition Policy.  Frederick R. Warren-Boulton. 1990. Implications of US experience with horizontal mergers and takeovers for canadian competition policy. The Law and Economics of Competition Policy."},{"key":"e_1_2_1_46_1","doi-asserted-by":"publisher","DOI":"10.1145\/2872427.2883028"},{"key":"e_1_2_1_47_1","volume-title":"The internet\u2019s original sin. The Atlantic 14, 8","author":"Zuckerman Ethan","year":"2014"}],"container-title":["ACM Transactions on Internet Technology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/3176246","content-type":"unspecified","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/dl.acm.org\/doi\/pdf\/10.1145\/3176246","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,6,18]],"date-time":"2025-06-18T19:04:50Z","timestamp":1750273490000},"score":1,"resource":{"primary":{"URL":"https:\/\/dl.acm.org\/doi\/10.1145\/3176246"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,8,7]]},"references-count":46,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2018,11,30]]}},"alternative-id":["10.1145\/3176246"],"URL":"https:\/\/doi.org\/10.1145\/3176246","relation":{},"ISSN":["1533-5399","1557-6051"],"issn-type":[{"value":"1533-5399","type":"print"},{"value":"1557-6051","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,8,7]]},"assertion":[{"value":"2016-11-01","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2017-12-01","order":1,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2018-08-07","order":2,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}]}}