Bluebeam, Inc.

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In short, Bluebeam makes smart, simple solutions for paperless workflows that leverage the PDF format. It all started way back in 1997, when we developed CAD to PDF creation technology for aerospace engineers. Now our award-winning PDF creation, markup and editing solutions are used by the world's top architecture, engineering and construction firms, as well as government agencies. We also have a strong following among tablet PC users, students and educators, accountants and even lawyers.

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We have departments that use Bluebeam at my place of employment. You can use the free version of this software to scale a project on a PDF document. For example, if you have a project picture of a Dresser, with no dimensions, you can assign a dimension to one side of the dresser case, and the software will use that scale factor to determine the rest of the dimensions of the project. It can only scale view-able lines and components.