The newspaper, citing people familiar with the matter, said the 57-year-old computer expert, who was born in Texas, changed her position in late 2021.
Forbes noted that Melinda’s fortune today is more than $6 billion.
The move followed her divorce last year from Microsoft co-founder Bill Gates.
The couple pledged in 2010 to give the bulk of their fortune to the Bill and Melinda Gates Foundation, which was founded in 2000 and has spent $55 billion in its first two decades, with a focus on fighting poverty, disease and inequality.