Court of Appeal judges considering a divorce case involving a housewife awarded £453 million are considering legal issues which could have implications.
Tatiana Akhmedova has been given a 41.5% share of Farkhad Akhmedov's £1 billion-plus fortune by Mr Justice Haddon-Cave after a hearing in the Family Division of the High Court.
Three appeal judges have analysed legal issues relating to a solicitor involved in the case at a Court of Appeal hearing in London.
Anthony Kerman, who had represented Mr Akhmedov at an early stage of proceedings, complained that he had been unfairly summonsed to give evidence at short notice during litigation before Mr Justice Haddon-Cave.
Barrister Philip Shepherd, who represented Mr Kerman, told judges Sir James Munby, Lord Justice Lewison and Lady Justice King that the appeal raised important issues concerning "legal professional privilege".
The three appeal judges are expected to publish their written analysis in the near future.
News of Ms Akhmedova's payout emerged during the summer of 2017 following a hearing in the Family Division of the High Court in London overseen by a High Court judge.
Mr Justice Haddon-Cave disclosed detail of the case in a written ruling published on a legal website.
Lawyers say the award is the biggest made by a divorce court judge in England.
A barrister representing Ms Akhmedova told appeal judges that Mr Akhmedov had not yet "paid a penny".