Facebook is testing the Header Bidding, a move to enter on the ad space of Google, at least within the big publishers. According to Cory Weinberg, on The Information, this is the next plan to expand Facebook ad network. A report confirmed also by AdvertisingAge.
Header bidding allow publishers to have multiple exchanges going to an auction in an ad space, so more advertisers will join the competition, which means more ad dollars to publishers. Before the header bidding technology, publishers only had one exchange, and the biggest was Google, with more advertisers bidding on it. Facebook can be a game changer introducing more competition, but where there is already some: in big publishers.
Facebook already tried in the past to join the programmatic business, when they bought the adserver Atlas, to Microsoft. However Facebook gave a step back on their DSP saying that the ad fraud was too high. So, the Header Bidding test does not guarantee that Facebook will enter in the programmatic market, as Facebook is moving back and forward. Another example was LiveRail, a video ad exchange bought also by Facebook, but closed years after.