Complex sentence: The company was the developer, owner and operator of the airport of the same name, however, it was now operated by its subsidiary HNA Infrastructure Co., Ltd. (formerly known as Hainan Meilan Airport).
Split into simpler sentences: The company was the developer, owner and operator of the airport of the same name. However, the airport was now operated by the company's subsidiary HNA Infrastructure Co., Ltd. (formerly known as Hainan Meilan Airport).