In order to maximize your revenue potential with the Ads for Adobe PDF service, it is very important to make it easy for people to find your PDF content and drive traffic to it.
Marketing Sherpa has a great article containing tips on how to ensure that your PDFs can be indexed by the search engines. I have included a summary below from a fellow blogger at Searchnewz:
Text Identification
In order to identify the text in an image in Acrobat, you would need to run OCR(character recognition) after opening your image-based PDF. Then go to the document menu, where it will scan the document and translate the image-text into text. You can then even edit the text according to your search engine optimization requirements.
Dividing the larger files
Dividing a large PDF file, into many smaller files would make it easier for the search engines to easily find your web page. By specifying your files, you can reduce the PDF download time, while you have the choice of opting for broader range of search keywords.
Optimize your PDF copy
After you have indexed the text PDF for search engines, you should also optimize the text with SEO techniques. Use specific keywords for the PDF and use them in the PDF text headlines, subheads and copy.
Discard duplicate content
You should be aware that the search engines simply hate duplicate content. So why bring the wrath of the search engines on you. Therefore, you should either alter one of same content that you have on the site, or delete it all together. Also, another option would be using proper meta tags. As it can prevent the search engines from indexing one of the pages.
Adding metadata
Another PDF technique would be adding text related Metadata. It would describe your file to the search engines and the search engines would use these information to index your page.
Adding links
In Acrobat PDFs you can add links, so that the customers can have a look at the product and can even add it to their shopping cart if they are interested.
Add your company footer
A company footer would include your companys name, address, contact information and website link. You can add these information to every PDF to facilitate searches for your business.
Optimizing links to the PDF
In order to convince, the search engines that your content is relevant, your website should have a display text containing the text specific keywords.