eBay Kleinanzeigen implemented prebid.js, an open-source header bidding solution, to enhance its programmatic advertising, resulting in a 22% increase in sales and a 51% improvement in viewability. The integration allowed for seamless competition among demand partners, reducing ad serving costs by 37% and optimizing loading times. Overall, the collaboration with AppNexus has proven highly beneficial in achieving eBay Kleinanzeigen's objectives in the programmatic media marketplace.

1. Case Study:AppNexus + eBay Classifieds | Powered by AppNexus | info@appnexus.com | www.appnexus.com | ©2016 AppNexus Inc. All Rights Reserved.
Solution: Prebid.js is an independent,open source header bidding project.
Start date: April 2016
BACKGROUND & SUMMARY
eBay Kleinanzeigen,Germany’s largest classified ads
marketplace and subsidiary of the global online marketplace
eBay,has been renowned as a pioneer in the programmatic
advertising space since 2012.
So when header bidding,a method also known as pre-bid,
emerged as the latest in programmatic technology,eBay
Kleinanzeigen recognized the opportunity to both secure their
place in the evolving advertising landscape and increase
revenue.Header bidding enables publishers to manage yield
at the impression level by moving the valuation process
ahead of the call to the publisher’s ad server.
Looking to ensure complete transparency and control for long
term success,eBay Kleinanzeigen sought an agile and complete
technology solution.They decided upon prebid.js,the
independent,open source wrapper supported by AppNexus.
Using prebid.js,a publisher can seamlessly integrate demand
partners directly into a website header to ensure fair and
transparent competition for their inventory without any
disruption to their partners’workflow.At the same time,
inefficiencies of the conventional waterfall model,such as
additional costs and longer loading times,can be avoided.
As a result,eBay Kleinanzeigen is now programmatically
selling its inventory more successfully than ever before.
OBJECTIVES AND CHALLENGES
eBay Kleinanzeigen sought a complete technology solution
to optimize its programmatic operations and increase
sales. Technology requirements included:
• Ability to integrate seamlessly into eBay Kleinanzeigen’s
existing infrastructure.
• An open and flexible solution that can be easily integrated
with additional demand partners to expand competition
and further optimize their revenue.
• Significantly improve the quality of impressions while
reducing loading time.
• Reduce the costs of ad serving.
• Deliver accurate reports,including the eCPM of each partner.
AppNexus +
eBay Kleinanzeigen
From the classic waterfall model to pre-bid: eBay Kleinanzeigen
increases programmatic sales by 22% and improves viewability
by an average of 51% through header bidding.
CASE STUDY - APPNEXUS + EBAY KLEINANZEIGEN

2. Case Study:AppNexus + eBay Classifieds | Powered by AppNexus | info@appnexus.com | www.appnexus.com | ©2016 AppNexus Inc. All Rights Reserved.
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RESULTS
After implementing prebid.js,eBay Kleinanzeigen’s
programmatic sales increased by 22%.Through further
optimization,a continued positive trend is expected.
eBay Kleinanzeigen also saw success in terms of
viewability and website load time.Integrating demand
partners into the website header – rather than using
a waterfall model,where one partner after the other
is called up – resulted in an average 51% improvement
in viewability.
There was also a noticeable increase in user interaction
with the website.The open source pre-bid technology
ensures simultaneous requests and a transparent auction
for all participants.As a result,passbacks are considerably
reduced,illustrated by a 37% decrease in ad serving costs.
In addition,this competition-focused approach also
resulted in a slightly increased eCPM.
Serhan Guenes,Head of Advertising and Partnerships
at eBay Kleinanzeigen,adds:“The programmatic media
business is extremely important to us,as we look to
continue to increase our sales.The independent,open
source pre-bid solution has hugely impressed us in terms
of achieving our objectives.Its adaptation options for
different partners offer huge potential,and the results
speak for themselves.Our collaboration with AppNexus
has been excellent from the outset.They have supported
us as both an independent technology provider and project
founder,even though they weren’t the only SSP in the
pre-bid set-up.”
SOLUTION AND IMPLEMENTATION
In order to increase eBay Kleinanzeigen’s sales,an in-house team assisted by AppNexus implemented the
header bidding solution,a process that took only a few weeks.Different adapters were implemented for
demand partners authorized by eBay Kleinanzeigen,allowing new partners to be integrated within a day.
Upon completion of the implementation stage,eBay Kleinanzeigen ran multiple tests,where traffic
controlled by pre-bid was steadily scaled from 1% up to 100%.
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3. Case Study:AppNexus + eBay Classifieds | Powered by AppNexus | info@appnexus.com | www.appnexus.com | ©2016 AppNexus Inc. All Rights Reserved.
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About eBay Classifieds
eBay launched its Kleinanzeigen portal in September 2009.The free,online classifieds
market is primarily geared towards private users and makes use of geographical
proximity and the resulting ability to establish personal contact.Categories range
from Family,Child Baby,House Garden,Leisure Community,Multimedia
Electronics and Cars,Motorcycles and Boats to Music,Film Books,and from
Fashion Beauty to Pets,Jobs and Property.
About AppNexus
AppNexus is an internet technology company that enables and optimizes the real-
time sale and purchase of digital advertising.Our powerful,real-time decisioning
platform supports core products that enable publishers to maximize yield;and
marketers and agencies to harness data and machine learning to deliver intelligent
and customized campaigns.Headquartered in New York City,AppNexus employs
over 1000 professionals in offices spanning five continents.
For more information,follow us at @appnexus
or visit our website at www.appnexus.com