This study examines the impact of the interactions of audit litigation and ownership structure on audit quality by Big 4 and non-Big 4 audit firms in Oman. This study uses modified audit opinion as proxies for audit quality, binary variable for audit litigation and percentage of shares owned by large shareholders and minority shareholders (consisting of Arab [non-GCC] shareholders) for ownership structure. The study uses size, risk, types of activity and ages of the firms as control variables. For the analysis and explanation of results descriptive statistics, correlation, regression techniques and T-test are used. Based on a sample of 107 listed companies on Muscat Securities Market (MSM) for 2013–2017, we find that audit litigation has a significant impact on audit quality for Big 4 audit firms, but not for non-Big 4 audit firms. Also, the results indicate that there is no difference between Big 4 and non-Big 4 audit firms as far as litigation risk is concerned.

本研究考察了审计诉讼和所有权结构的相互作用对阿曼四大和非四大审计公司审计质量的影响。本研究使用修改后的审计意见作为审计质量的代理，审计诉讼的二元变量以及大股东和小股东（由阿拉伯 [非海湾合作委员会] 股东组成）拥有的股份百分比作为所有权结构。该研究使用公司的规模、风险、活动类型和年龄作为控制变量。用于结果描述性统计、相关性、回归技术和T的分析和解释- 测试被使用。基于 2013-2017 年马斯喀特证券市场 (MSM) 107 家上市公司的样本，我们发现审计诉讼对四大会计师事务所的审计质量有显着影响，但对非四大会计师事务所没有影响。此外，结果表明，就诉讼风险而言，四大会计师事务所和非四大会计师事务所之间没有区别。