Adobe has discontinued their PDF Ads program blaming the current state of economy. The advertising program was launched exactly an year ago and allowed content owners, both big and small, to monetize PDF content through contextual text ads that were supplied by Yahoo.
That may be a reason but more than that, none of the big publishers like O’Reilly, IDG, etc. got attracted to the Adobe PDF Ads program and revenue generated from small PDF publishers was probably not very exciting for Adobe to continue their advertising relationship with Yahoo.
If you were part of the Adobe program and have distributed ad-enabled PDFs on the web, the Yahoo! ads will continue to display in your PDF until March 31 after which Adobe will discontinue delivery of ads though the PDF files can still be read inside Adobe Reader.
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