The deal, expected to complete on Nov. 1, will give Nine 100% ownership and help Nine with its expected share flotation on the ASX. Financial terms were not disclosed.
"Mi9 will continue to represent Microsoft's suite of advertising products, while leveraging their world leading technology, data, insights and innovation. This agreement allows [Nine] to retain the key elements of our almost two decade strategic partnership with Microsoft. It strengthens the platform for NEC's growing digital video business and ultimately allows us to control 100% of our digital future," Nine's CEO David Gyngell said in a statement.
Exiting the Australian media business also fits with Microsoft's growing emphasis on devices and services over software and media.
NineMSN was formed by James Packer in 1997 as a partnership between Nine's former owner Publishing and Broadcasting Ltd and Microsoft, operating news and entertainment websites and consumer and advertising data services.