Header bidding has emerged as a workaround for publishers and advertisers to sell and buy ad impressions programmatically. Before the technique was introduced, as you know, publishers had to rely on the traditional waterfall method where demand partners are called in sequential order.
Unlike waterfalling, header bidding enables the demand partners to compete simultaneously and drives up ad revenue. It’s win-win for both publishers and advertisers — for publishers, more demand partners bring more ad revenue and for advertisers, better/equal opportunities to reach sellers.
Initially, header bidding was developed to increase the yield for publishers by monetizing the display ad inventories. Of course, the technique held onto its share of the programmatic display, but it’s been gaining momentum in the programmatic video as well.
So, this article aims to cover the essential video header bidding concepts including:
- Different methods of video header bidding and how they work,
- Pros and cons of server-side and client-side video bidding,
- Challenges faced by the publishers with video header bidding and how to overcome them, and
- Benefits of video header bidding.
Let’s start with the basics of video header bidding.
What is Video Header Bidding?
Video header bidding opens up the video ad impressions to multiple demand partners simultaneously before sending the requests to the ad server. However, there is one major difference between the execution of display and video header bidding – positioning of the wrapper.
In display header bidding, the wrapper is added to the header of a webpage. However, there are no header tags in a video player as it’s just another piece of JS. So, video header bidding can happen
a. When the video player starts loading. In fact, there’ll be no auctions until the user clicks the play button. In other words, header bidding will happen when the video player is loading to display the content.
b. When the header of the page loads. Yes, you can still run the auctions when the header loads and pass the values to the video player. That’s how Prebid’s video header bidding works. We’ll dive into the details later in the post.
There are two types of video header bidding: Server-side and client-side. And, the workflow differs slightly from each other. That being said, let’s understand how each type works in detail.
How Does Video Header Bidding Work?
Similar to display header bidding, server-side video header bidding takes place in the ad server whereas client-side occurs at the browser of a user. But, video header bidding has one extra participant in the whole process – video player. Hence, we cannot skip the process completely. So, let’s see how both the types work.
- When a user loads a player (or a page — depending on the implementation), the header bidding wrapper calls the SSPs or Ad Exchanges which further sends a bid request to the video demand partners for the bids.
- Once the demand partners send the bid responses, the SSPs or Ad Exchanges pass it to the header bidding wrapper.
- The wrapper evaluates the bids received within the specified timeout (for example, 500ms) and passes the highest bid to the publisher’s ad server (via the video player).
- Then, the ad server compares the bid received with the bids with guaranteed and other non-guaranteed line items (Google AdX bids).
- After comparing all bids, the server selects the highest bidder and sends the video ad creative to the video player.
- At last, the video player displays the ad to the user.
- When a user loads the player, the header bidding wrapper requests the server-to-server header bidding vendor to initiate the header auctions. The s2s vendor calls the demand partners as usual.
- The bid responses from the demand partners will be passed down to the S2S vendor.
- The vendor then passes the winning bid to the wrapper, which, in turn, sends it to the publisher’s ad server.
- Then, the server compares the bid value with the bids received from PMP deals, direct deals, and Google AdX.
- Ad server select’s the highest paying bid and sends the video ad creative to the player. The player runs the ad.
Note: It isn’t necessary to have a separate ad server and s2s header bidding vendor. A publisher can use their primary ad server to run server-side bidding. For instance, Google’s open bidding. Google acts as an S2S vendor as well as the publisher’s ad server. Also, in open bidding, there is no wrapper.
How Video Header Bidding takes Place via Prebid.js?
Though the above-mentioned steps sound quite easy to understand and get started with video header bidding, the process is much more complicated than it seems. But why? Because video ads require additional attributes such as VAST to extract the creatives. Technically, this is how client-side in-stream video header bidding takes place if it’s done via Prebid:
- Prebid.js loads within the header of a web page, and calls the video demand partners for a bid response.
- The demand partners return the bid response that consists of bid price and video ad creative. Unlike display creatives, video ad creatives are sent in the form of a VAST URL (VAST URL returns a VAST XML wrapper).
- The Prebid.js receives the bid response, and stores it in the server after mapping each bid to a Cache ID*. Prebid then creates a new master video ad server tag URL by combining existing video ad server tag with Prebid key-value targeting pairs.
- This URL is passed to the player and the player runs the master video ad server tag URL to make the call to the server.
- Once the ad server receives the highest bid response, it matches the bid value with the pre-configured line items. It compares the bid with bids from other line items and selects the winning line item. The line item’s VAST creative is sent to the wrapper.
- Wrapper sends it to the video player to render the ad creative.
Sounds a bit complex? Yes, it is. And, that’s why publishers find video header bidding more challenging as compared to the display header bidding.
Challenges Faced by the Publishers
According to a survey done by Forrester, publishers face the following challenges in video header bidding:
Programmatic industry changes rapidly making it difficult for the publishers to catch up with the technologies. There are multiple video ad formats, sizes, processes, etc. that are critical to understand. Hence, it is recommended to start video header bidding under the guidance of an expert who can help you with the technicalities.
Given the myriad of challenges, if you implement video header bidding properly under the right conditions and guidelines, it will not be as daunting as it seems. Besides, the results can be much better than display header bidding.
Benefits of Video Header Bidding
Publishers who monetize their video ad inventories via header bidding can get:
- Maximized ad revenue – Video CPMs are much higher CPMs and video ads have better CTRs than display ads, and implementing header bidding on video inventories can drive better yield. According to the survey, 61.3% of the publishers said the video header bidding improved the ad revenue.
- Better ad fill rate – According to the survey, 57.7% of respondents said that header bidding in video ads improved the ad fill rate. As the video demand is scarce, implementation of the technique helped the video content publishers to bring more demand and hence improved ad fill rate. Also, 53.6% of the total respondents said that video header bidding improved demand optimization.
- More Transparency: Header bidding enables the publishers to check how their bidders are performing via several channels such as analytics tools, Google Ad Manager reports, etc. Besides, Prebid is an open-source for publishers that enables them to create a transparent platform as they can see how auctions are happening. However, S2S video header bidding has transparency issues as the auction happens inside the ad server. But, the client-side will help you to get more transparency.
Video header bidding has improved a lot in the past few years and it will contribute significantly to programmatic advertising in the future. As of now, 66.6% of total video publishers have implemented the header bidding to monetize their video ad inventories. Also, 11.7% are ready to start with it in the next 12 months.
Want to give it a try? Then, we have a list of SSPs, Ad Exchanges, Video Players, and Video Ad Networks in place for your reference. But, in case, if you’re not sure whether video header bidding is right for you or not? Get in touch with us today. Or you can ask any ad ops questions via AdOps Quick Fix. We’ll try to get the answers as soon as possible.