Ask the Audience: 3 Key Questions from our Header Bidding Webinar

With all that buzz, it’s no surprise AppNexus’ header bidding webinar was such a big hit last week. Hundreds of ad ops pros attended as we covered everything from header bidding auction mechanics to successful implementation. You can watch a recording here if you were unable to attend live.

While 96 percent of our audience told us they learned something new about header bidding, they were still curious enough to ask some great questions during our lively Q&A session. are three of the best, along with some answers you’ll find helpful.


Question 1: How do I deal with demand partners who want to work outside of a wrapper?

Short answer: Don’t.

Long answer:

First, let’s have a quick refresher on what a header bidding wrapper, or container, actually is.

With header bidding, publishers can have their record a demand source’s bid in real time, by adding a few lines of Javascript to their sites. The problem is that if publishers have to add Javascript for every single demand source they work with, it can cause latency. Not to mention, writing that new code, maintaining it throughout software updates, and creating unique line items for each partner is time consuming and causes resource constraints.

Enter the header bidding container. It’s just another piece of code that contains all the possible demand sources and enables a publisher’s web site to easily call them to auction off impressions.

Going back to the original question, ask yourself: Why would a firm want to cut itself off from such a useful tool? Header bidding wrappers aren’t complicated or risky pieces of technology, which is why so many publishers have embraced them. Plus, if you use an open-source solution like Prebid.js, you have access to an entire community building free add-ons and making sure the container stays clean and efficient.

As a publisher, your webpages don’t belong to anyone but you. So, if a potential demand partner says you need to let them operate outside of a wrapper in order to do business with them, tell them no. Or better yet, invite them to build an adaptor that would let them connect to an open source container like Prebid.js.


Question 2: Should I randomize the order of my bidders to provide a level playing field?

Short answer: Yes.

Long answer:

You might not think that it matters in what order your header bidding container calls all your demand sources. These auctions take place in milliseconds anyway, right?

In reality, that order can matter greatly. The Prebid.js community has noticed that the last demand source called has a much lower chance of winning an impression. It makes sense: If a publisher has their timeout settings optimized, each demand partner has a short amount of time to place a bid, so every millisecond counts.

That’s why we recommend you randomly shuffle the order in which bidders are called. Doing so guarantees that in the long run, none of your demand sources are at a disadvantage in vying for your audience’s attention. That means more robust competition and fosters a healthier working relationship with each of your partners. The community at Prebid.js has made this tactic extremely easy to implement.


Question 3: How can we ensure buyers aren’t competing against themselves by bidding on multiple SSPs?

Short answer: That’s the buyer’s responsibility. For now.

Long answer:

No one wins when advertisers bid against themselves through multiple SSPs. In the short term, the heightened competition might drive up the price a publisher can get for an impression.

However, in today’s world, buyers who are integrated on multiple exchanges need to be the ones making sure that they’re not bidding against themselves. As more and more advertisers realize that header bidding isn’t going anywhere, they’re embracing it and optimizing their bidding setups accordingly.

One day, we think that responsibility could fall on SSPs themselves. Buyers are trying to get their ads on thousands of different domains and the paths to doing it are becoming more and more complex. Soon, it will be too much for buyers to oversee manually, and they’ll need to rely on SSPs that can actually manage inventory.


A tool like header bidding improves monetization for publishers and makes auctions more open for advertisers. It’s a game changer, so it’s sure to inspire questions from both sides of the table. These are just three of more than ten insightful questions we fielded during last week’s webinar.

Want to hear the rest of those questions and check out the webinar itself? Watch the recording here.

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