In an RT-PCR/Sanger sequencing survey of serous ovarian cancers at two different institutions, we confirmed ESRRA-C11orf20 fusion transcripts in 10 of the 67 tumors, or 15% (95% confidence interval: 7% to 26%), suggesting that this fusion is present in a significant fraction of serous ovarian cancers. The gene discussed is ESRRA; the disease is ovarian serous adenocarcinoma.