It was temporary.
MM's are the ones who are probably shorting. They're the only ones really capable of it. A short is selling shares you don't actually have. At some point, you have to buy back the amount you sold to cover your fictional sale. There is a lot of risk in shorting because unlike buying, when you short, you can lose more than your investment. Since most pinks fail, shorting is disallowed or we'd all be rich off of bankrupt companies.
News 
Market Data 
Discover 
