Pay Per View and Search Engines

Hi folks,

Important question here . . .

On most articles there will be a limit to how much of the article people/humans will see. Before they see the entire article, they will need to pay on one of the Pay Per View plans.

Some (just a handful will show the entire article free fyi).

Important Question is: How can me allow all search engines to see the entire content (i.e. non-human search engine crawlers to determine ranking and content under the above setup)? It is important to allow search engines to see ALL the content.