PDF files don't offer many options for marketers, but Yahoo! is hoping to change all that in a new deal with Adobe to insert dynamically generated ads into the popular document format.

According to a story in The Washington Post, both companies are expected to announce Ads for Adobe PDF Powered by Yahoo sometime tomorrow. A limited beta program will follow the announcement.

The new tool will allow advertisers to insert dynamic ads into PDFs housed online or in emails. Previously, PDFs had only allowed for static advertising.

For now, Yahoo is Adobe's only ad partner for dynamic PDF ads, giving the internet giant an early lock on a new advertising channel.