SharePoint 2013 & SharePoint Online: How many co-authors can work on the same Office Document?

In SharePoint 2013 OnPremises the maximum number of authors in an Office Document is configurable as It’s stated in the following TechNet Url: http://technet.microsoft.com/en-us/library/ff718248(v=office.15).aspx. Therefore, we could understand that there isn’t a limit regarding to this setting…and we would wrong. Fortunately, in the SharePoint Software boundaries and limits article we can find a partial answer to this question (http://technet.microsoft.com/en-us/library/cc262787.aspx):

• The recommend co-authors number in a single Word or PowerPoint document is 10.
• And the maximum number of co-authors in a single Word or PowerPoint document is 99. It’s not possible to overpass that limit since it’s a threshold.

However, I’m not 100 % sure if these limits are also applicable to other Office products where co-authoring is also possible: http://technet.microsoft.com/en-us/library/ff718249(v=office.15).aspx

Finally, let me share with you a PowerShell script that allows to read and update this setting for a given Web Application in a SharePoint 2013 farm:How to read and modify the maximum number of co-authors for Office documents