At a Business Insider event in Berlin last April, Jeff Bezos said MacKenzie's support was instrumental when he founded Amazon as an online bookseller in 1994, and that she did the accounting for the company in its first year.

"When you have loving and supportive people in your life, like MacKenzie, my parents, my grandfather, my grandmother, you end up being able to take risks," he said at the event.

A divorce could reshape the world's wealth rankings. If the couple split their fortune equally, it would make MacKenzie the world's richest woman. It would also make Microsoft co-founder Bill Gates the planet's richest person once again.

The state of Washington – where Amazon is based and where the couple has a home – is a community property state, which means all property and debt acquired during a marriage "will be divided equitably by the court if the couple cannot negotiate an agreement," according to the website of McKinley Irvin, a family law firm in the region.

From modest beginnings as an online bookseller, Bezos and Amazon branched out into almost every product category available, ending up taking on established retail giants such as Wal-Mart.

Under Bezos, Amazon launched the Kindle e-reader and revolutionised the way books are distributed and read. The company has also been a pioneer in cloud computing.

In November, Amazon picked America's financial and political capitals for massive new offices, branching out from its home base in Seattle with plans to create more than 25,000 jobs in both New York City and an area just outside Washington, D.C.

Reuters