Even though Skype for Business is a premium offering for Microsoft, it has it’s own limits. There are limits to the number of participants, presenters and the file size which can be uploaded in a meeting.
The Maximum number of participants in a Skype for Business Conference is 250. This can also be said for the Maximum number of Presenters. The Maximum File Size that can be uploaded in a Skype for Business Meeting is 500 MB. However, there is no limit to the size of the file which can be sent over an IM.