http://proofhq.com/index.html

It is really cool that they just focus on one thing: proof. However, they just do PDF and several image file formats. They should do Microsoft file formats as well, especially Word documents, since these file formats are most widely used.

I assume they start from PDF and image file formats because these file formats are easier to start from. If this is the case, Microsoft file formats should be in their pipeline. The good thing is, their jobs may become easier since Microsoft recently opens those Office binary formats.

Anyway, I will track this startup closely. Thanks for sharing.