SharePoint 2007/ 2010 mainly used for documents management and collocation; including all the features (Check In, Check Out, Version History, etc...) using Microsoft Office Suite. By default SharePoint does not support these features for PDF files. Adobe has released a product called Adobe Acrobat X which you can use it to achieve a good integration with SharePoint and use all its features Check In, Check Out, and Collect Feed back workflows. The following screenshots show some of its features [1].
Figure (1) Open and Check out file
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