The Grosvenor Estate, which owns the Grosvenor Group is owned by the
Duke of Westminster
Upon his father’s death in August 2016, the Duke inherited, as well
as the peerages, a wealth then estimated at £9 billion, with
considerable trust funds for his sisters.[7] This wealth is held in a
trust, of which the 7th Duke of Westminster, as he became, is a
beneficial owner but not the legal owner—an arrangement that received
considerable media attention, owing to the inheritance tax exemption it
confers. — Wikipedia