Publicis will acquire Razorfish, a Microsoft-owned digital and interactive shop, for roughly $530 million, according to joint company statements (pdf here).

Razorfish will continue to operate under its brand name, and retain its management structure, led by CEO Bob Lord. David Deal, a Razorfish spokesperson, said the agency is anticipating “business as usual for Razorfish, including our health practice, and we do not foresee sweeping changes otherwise.”

Publicis will integrate Razorfish into its newly created VivaKi group, which incorporates digital and media assets such as Digitas and Denuo into a “nerve center,” tasked with global talent development and the creation of “a new approach to strategic scale across platforms, partners and technology,” according to the VivaKi website.

The acquisition follows a partnership between Publicis and Microsoft that was announced in June, allowing several of Publicis’s agencies within the VivaKi group – which also includes Starcom MediaVest Group and ZenithOptimedia – to use Microsoft’s Admira technology for media planning, buying and measurement. Admira is slated to launch during the fourth quarter of this year.

Razorfish’s clients include Wyeth, Schering-Plough, Johnson & Johnson and others. The agency has hinted at formalizing its healthcare operations in recent months, but has been unable to comment on that development.