There are only 3 platforms where simultaneous user limits for ebooks can come into play. All others have downloadable PDFs that unlimited users can access and keep forever.
The 3 platforms are EBSCO, ProQuest, and Digitalia Hispanica. They are detailed here on our Digital Rights Management page.
There's no way to display in searches in Discovery Search or the Ebook Title Database what restrictions apply to an ebook, because they vary based on how they were purchased (and often how long ago). Frequently, but not always, EBSCO and ProQuest will show on the ebook's home page the limits (1 user, 3 users, "nonlinear lending," etc.).
If you've found an ebook on one of these 3 platforms you want to use for a class, email the Library's Electronic Access Team at eataccessproblems@vt.edu and we'll look in the purchasing system to see what restrictions are in place and if we can either upgrade the ebook or purchase it on a platform without restrictions.