Aside from job security, questions swirl around the deal's terms and the impact on AppNexus, details of which are being held close to the vest.
Sources say as few as five executives were direct party to the negotiations, among them AOL's Armstrong and Lord, Microsoft corporate VP Rik van der Kooi, AppNexus CEO Brian O'Kelley and AppNexus President Michael Rubenstein.
While the rough outline of the agreement is clear, many of its particulars are not. Here are just a few unanswered questions: Will AOL acquire assets from Microsoft, along with the right to sell its inventory? Does the deal come with cash payments? What's the revenue share? And did Microsoft issue revenue guarantees to AOL, as it did under its 2009 search alliance with Yahoo?
For now, the companies have declined to comment further.
With regard to AppNexus, Microsoft's van der Kooi emphasized nothing will change in the near term with regard to the programmatic platform's access to Microsoft inventory. However, there may be a risk to AppNexus in the long haul. After all AOL has an ad tech stack of its own, one that includes a sell-side platform with some of the same functionality AppNexus offers, run by longstanding AOL exec Dave Jacobs.
There was a degree of king-making that happened when Microsoft invested $100 million in AppNexus, back in 2010, and made the exchange platform its partner for all Microsoft programmatic sales across at least 39 markets where it operates. Should that partnership partially unravel, it would significantly hurt AppNexus.
How likely is that to happen? One rumor circulating at Microsoft is that AppNexus is protected for a period of one year, after which time AOL and Microsoft will conduct a review of their programmatic partner options in the nine global markets covered by the deal. After that year, the Microsoft inventory could either stay with AppNexus, migrate to AOL or go to an outside partner.
Should AOL attempt to migrate a portion of Microsoft's supply to its own pipes, it will come as a blow to AppNexus, which is valued at more than $1 billion and is expected to IPO in the first half of 2016.
Meanwhile, outside of Microsoft's top nine markets, Microsoft and AppNexus have expanded their agreement, making all Microsoft inventory in countries such as Finland, Ireland and Austria programmatically traded.
"In our next 10 markets in Western Europe mostly, we're going all in on programmatic,” van der Kooi said, “partnering even more deeply with AppNexus than we are today."