Cleber acted as Dutch co-counsel in arbitrations before a distinguished NAI tribunal representing Angolan State-owned Sonangol against companies of Isabel dos Santos, the daughter of the late president of Angola. In the most important of the set of arbitration cases the tribunal found in its final award of 23 July 2021 that the acquisition by a company beneficially owned by Isabel dos Santos and/or her late husband Sindika Dokolo of a shareholding in Esperaza Holding B.V., a Dutch intermediate holding company, from Sonangol constituted an act of ‘grand corruption’ and was hence void as contrary to public order. The award https://jusmundi.com/en/document/decision/en-exem-energy-v-sonangol-i-award-tuesday-27th-july-2021 has been cited as exemplary in dealing with transactions involving corruption at the highest levels of a state.