For a case study, I want to upload a PDF article and have my students discuss it by group, by highlighting and adding comments to the PDF. Let's say I have 5 groups in the class. Can I perhaps make 5 copies of the article and give one copy to each group? The students should then only be able to access the copy of their group. 

I know that Canvas has an option to make a group assignment, but it is only available if the submission type is online. I don't know how to combine any of the online submission types (text entry, website URL, media recording, file upload) with collaborative pdf annotation.