A binding agreement to merge DEA and Wintershall was published on 27 September 2018.[34] The merger was carried out with official approval in May 2019.[35] It created Europe’s leading independent gas and oil company.[36] BASF holds 67 % of Wintershall Dea and LetterOne holds 33 % of the ordinary shares in Wintershall Dea.[37] To consider the value of the midstream business of Wintershall Dea, BASF further received preference shares which results in a current overall participation of BASF of 72.7% in the entire share capital of the Company.[38] The preference shares will convert into ordinary shares of the Company on May 1st, 2022 or upon an initial public offering, whichever comes earlier.[39]