The Impact of Mandatory Sustainability Assurance on Reporting Credibility in the Amman Stock Exchange

Abstract Objectives: This study examines the causal impact of mandatory sustainability assurance on the credibility of sustainability reports in an emerging market context. Specifically, it evaluates the regulatory reform introduced by the Jordan Securities Commission in 2023, which mandates external assurance for sustainability reports of firms listed on the Amman Stock Exchange with market capitalization exceeding JOD 100 million. The objective is to provide structured evidence on how regulatory intervention influences reporting quality, audit effort, and capital market outcomes. Data description: The dataset comprises 110 firms observed over the period 2020–2024, resulting in 550 firm-year observations. The data include measures of sustainability reporting quality based on SDG disclosures, assurance fees, number of assurance procedures, cost of equity, and proxies for information asymmetry. Additional variables capture corporate governance characteristics such as audit committee expertise and ownership structure. The dataset enables analysis of pre- and post-regulatory changes and supports causal inference using difference-in-differences and related methods. Limitations - Sample limited to Jordan - Time period restricted to 2020–2024 - Availability of sustainability disclosures varies across firms JEL Classification: M42, M48, G34, G38, Q56