Complex sentence: EasyGroup (styled as easyGroup), founded in 1998, is a conglomerate & the holding company controlling the "easy" ventures; it is privately owned by Stelios Haji-Ioannou.
Split into simpler sentences: EasyGroup (styled as easyGroup), founded in 1998, is the holding company controlling the "easy" group of companies. It is privately owned by Stelios Haji-Ioannou.