Sentence:  Tickets sold online through Craigslist, eBay, and other forums, where the purchaser cannot physically see them, run a greater risk of being counterfeit—but counterfeiters have been known to <WSD>scalp</WSD> tickets in person outside the venue as  well, ... 
Meaning of the word marked with <WSD> tags:  To resell, especially tickets, usually for an inflated price, often illegally.