The Turkish government attempts to have him and extradited to face trial were blocked by the UK courts in April.
The group includes interests in the mining, media and print, aviation, agriculture, health and insurance sectors.
He served as president of the Board of Directors of Koza Anadolu Metal Madencilik İşletmeleri A.Ş.
and İpek Doğal Enerji Kaynaklari Araştırma Ve Üretim A.Ş., three publicly traded companies on the Istanbul stock exchange with diverse interests in print, mining and energy.
Other notable positions held by Mr Ipek were the presidency of the board of ATP İnşaat Ve Tic A.S., a construction and commerce company; Koza Ipek Sigorta Aracılık Hizmetleri A.Ş., an insurance brokerage firm; and the chairmanship of ATP Havacılık Ticaret A.Ş., an aviation commerce company.