This is a list of airline holding companies, that either own more than one airline or are the parent company of a single airline. A company or firm in which the holding company owns a significant portion of voting shares, usually 20–50% or a "minority of share ownership", is known as an associate company. A company in which the holding company owns more than 50% voting shares or a "majority of share ownership" is known as a subsidiary. The holding company thus can also be referred to as the parent company at that stage.