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This content will become publicly available on November 8, 2025

Title: On the Use of Proxies in Political Ad Targeting
Detailed targeting of advertisements has long been one of the core offerings of online platforms. Unfortunately, malicious advertisers have frequently abused such targeting features, with results that range from violating civil rights laws to driving division, polarization, and even social unrest. Platforms have often attempted to mitigate this behavior by removing targeting attributes deemed problematic, such as inferred political leaning, religion, or ethnicity. In this work, we examine the effectiveness of these mitigations by collecting data from political ads placed on Facebook in the lead up to the 2022 U.S. midterm elections. We show that major political advertisers circumvented these mitigations by targeting proxy attributes: seemingly innocuous targeting criteria that closely correspond to political and racial divides in American society. We introduce novel methods for directly measuring the skew of various targeting criteria to quantify their effectiveness as proxies, and then examine the scale at which those attributes are used. Our findings have crucial implications for the ongoing discussion on the regulation of political advertising and emphasize the urgency for increased transparency.  more » « less
Award ID(s):
2318290 2344925 1956435
PAR ID:
10565426
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
Association for Computing Machinery
Date Published:
Journal Name:
Proceedings of the ACM on Human-Computer Interaction
Volume:
8
Issue:
CSCW2
ISSN:
2573-0142
Page Range / eLocation ID:
1 to 31
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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