New Post: Do you need a license to create OpenXML files ?

Hi everyone,

I'm not sure if this question was already asked but I didn't find anything.

My problem is: Because of the controversies around the OpenXML format, I'm not sure how it actually is patented/licensed.
Can someone tell me how far I can go with ClosedXML applications creating OpenXML files ?
For example, is it legal to distribute it/profit from it ?
I'm not talking about the MIT license for ClosedXML which I'm aware of, but in general about the fact that I'm distributing a file written in a proprietary format but not created by the proprietary software.
Maybe this question is dumb, but I was just wondering :)

Thanks,

Matthias