I have a fairly large font collection that has grown over the years. Most of the fonts that I have were purchased by me or an agency. However, some have been traded between me and other designers (gasp). I have come to realize that some of these font sets are not legit.
Apparently, hackers are rebuilding fonts from stolen sources such as .TTFs, WOFFs, EOTs and PDFs. In these cases, the kerning is not set properly and many glyphs are often missing. What is the best way to check to see if a font set is legit?