To assess the role of germline pathogenic variants (PVs) in SMARCA4 and further established ovarian cancer (OC) predisposition genes in early onset OC, we investigated a clinical cohort of 206 unrelated OC index patients with an age at diagnosis of OC ≤40 years using an extended panel of 24 (candidate) cancer predisposition genes. Here, SMARCA4 is linked to ovarian carcinoma.