When Microsoft acquired advertising services holding company aQuantive for $6bn in 2007, Microsoft CEO Steve Ballmer hailed the acquisition as “the next step in the evolution of our ad network“.

The deal gave Microsoft aQuantive’s three holdings: Avenue A/Razorfish, Atlas Solutions, and DRIVE Performance Solutions.

According to the Financial Times, the next step in the evolution of Microsoft’s advertising business is the divesture of digital agency Avenue A/Razorfish, now called Razorfish. FT.com reports that Microsoft has retained investment bank Morgan Stanley to shop Razorfish to interested parties.

Publicis Groupe is said to be one of the likely potential buyers. Publicis’ CEO, Maurice Lévy, has stated that his company may be in a buying mood after a refinancing this month and he stated “Obviously if we can take advantage of the current situation to be ready to take
these things
“, referring to the global economic downturn that has roiled the ad market.

One analyst the Financial Times spoke with pegged Razorfish’s valuation at $600-$700m, down from the $800m valuation AdAge gave to Razorfish last year.

This isn’t the first time Microsoft has reportedly looked to rid itself of Razorfish. Others have noted that owning a digital agency like Razorfish presents some problems for Microsoft and last year rumors circulated that the Redmond giant was shopping the company.

We’ll see if in 2009 it finally pulls the trigger.

Photo credit: Robert Scoble via Flickr.