Big difference, Facebook has been in business for years and has an established product. OTC securities are start ups and abuse exemptions by using illegal activities to fund their business.
Hedge funds could not short FB, look up the rules on IPOs, there is no shorting allowed on IPOs for a period of time.
Glitch? They happen and yet it was admitted to and is being mitgated with paying for those losses caused by the trading issues experienced.
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