Cape Town – Judge Taswell Papier found Nomfundo Mtshawu and Vuyolwethu Mgemane guilty of the murder of former Naspers financial director Eric Wiese in the Western Cape High Court on Tuesday.
The Gugulethu couple, who have a child, had attacked Wiese, who retired in 1998, in his Higgovale home on August 4, 2017.
They tied him up and stole items to the estimated value of R25 000. His death was attributed to "manual strangulation".
Expressing relief, his widow, Sannie Wiese, who was married to the deceased for 52 years, told News24: "Our legal system still works and I am satisfied."
She had been out shopping for her son's birthday celebration at the time of the incident and returned to find the house in disarray and drops of blood on the floor. After calling a security company, they found his body next to a bed.
Mgemane previously admitted to strangling Wiese with a tie "because he was resisting". He had asked the family for forgiveness.
Neither of the accused presented evidence in their defence. They were caught on CCTV footage at the house.
Given Wiese's physical stature, Judge Papier found it would have been impossible for Mgemane to subdue and tie up Wiese without her assistance.
Mtshawu has three previous convictions for theft, while Mgemane was previously convicted of two housebreakings, theft, robbery and possession of a dangerous weapon.
The case was postponed to August 1 to obtain a probation officer's report. They will remain in custody.