Ad network operator Proximic has signed deals with Yahoo and eBay to stream listings on Proximic's network.

Listings from Yahoo Shopping and Shopping.com — which is owned by eBay — will now appear across Proximic ad space. The network allows blog and website publishers to place an ad widget on their sites to display relevant ads.

Ads from Proximic differ from other contextual ads in that they're based on patterns of text that appear on the webpage, instead of keyword matching. That, the company says, allows for closer ad integration to what is actually being read.

The deal represents the first time Yahoo or eBay have syndicated their listings. It also adds 50 million prospective listings to Proximic's inventory instantly, broadening opportunities for matching product to appropriate content.