The Abu Dhabi National Oil Co (ADNOC) raised $2.5 billion from the IPO of its gas business, ADNOC Gas, making it Abu Dhabi's largest IPO. The IPO was for a 5% stake, valuing the company at about $50 billion. The company's low-carbon intensity energy asset base attracted strong interest in the IPO, ADNOC Group Acting CFO Khaled Al Zaabi said.