Complex sentence: Urs Ernst Schwarzenbach, CStJ (born 1948) is a Swiss financier who has been the subject of extensive publicity regarding a tax fraud and the seizure of certain of his assets by raids conducted by the authorities due to unpaid taxes.
Split into simpler sentences: Urs Ernst Schwarzenbach, CStJ (born 1948) is a Swiss financier. In April 2015, the "Sunday Times" estimated his net worth at £1.0 billion Recently he has been the subject of extensive publicity regarding a tax fraud and the seizure of certain of his assets by raids conducted by the authorities due to unpaid taxes.