According to Nielsen//NetRatings data, the following advertisers purchase the largest amount of ad impressions on Google:
- eBay - 984.2 mln impressions in January 2006
- Shopping.com - 447.59 mln
- Local.com - 279.25 mln
- Target - 218.14 mln
- Expedia - 197.33 mln
The following advertisers bought the largest amount of impressions on Yahoo! search engine.
- eBay - 537 mln impressions in January 2006
- Shopping.com - 501.2 mln
- University of Phoenix - 151.64 mln
- LengingTree - 116.3 mln
- Target - 79 mln.