Shielding citizens? Understanding the impact of political advertisement transparency information

Online targeted advertising leverages an information asymmetry between the advertiser and the recipient. Policymakers in the European Union and the United States aim to decrease this asymmetry by requiring information transparency information alongside political advertisements, in the hope of activating citizens' persuasion knowledge. However, the proposed regulations all present different directions with regard to the required content of transparency information. Consequently, not all proposed interventions will be (equally) effective. Moreover, there is a chance that transparent information has additional consequences, such as increasing privacy concerns or decreasing advertising effectiveness. Using an online experiment (N = 1331), this study addresses these challenges and finds that two regulatory interventions (DSA and HAA) increase persuasion knowledge, while the chance of raising privacy concerns or lowering advertisement effectiveness is present but slim. Results suggest transparency information interventions have some promise, but at the same time underline the limitations of user-facing transparency interventions.