The widow of Queensland mining magnate Ken Talbot is taking legal action in a Brisbane court over the estate of the Macarthur Coal founder who died more than a decade ago.
Amanda Talbot is suing Boyd Legal over allegations owner Bill Boyd failed to finalise her husband's new will before he died, causing her to lose financial benefits.
A trial, expected to last at least three weeks, started in the Brisbane Supreme Court on Monday.
The Macarthur Coal founder died in June 2010 when his plane crashed in the Republic of Congo.
The BRW Rich 200 list cited Mr Talbot's worth at $965 million at the time of his death.
He was described as one of Australia's greatest entrepreneurs in court.
The businessman had been married to Ms Talbot since April 1995 and the couple had two children, Alexandra and Claudia.
Mr Talbot also had two children Liam and Courtney from a previous marriage.
Mr Boyd was retained by Mr Talbot in various capacities over 15 years up until his death.
This included preparing his will in 2002.
Mr Boyd was also administrator of Mr Talbot's estate from June 29, 2012.
Ms Talbot claims Mr Boyd had been engaged by her husband in late 2007 to create a new will and the lawyer failed by not having the process completed when Mr Talbot died.
The court was shown an email to Mr Boyd in December 2008 in which Mr Talbot asked about progress of the will, saying: "We should aim to knock it off the table."
But discussions about the will continued with further correspondence and meeting notes shown to the court.
Ms Talbot argues the delay cost her money as a beneficiary of her husband's estate.
The trial continues before Justice David Boddice.