It isn't always the result of shorting. Sometimes they can run the company to the ground. Also lets say they short at .05 and buy back at .025 they've made money and there wasn't a squeeze. It is when the price starts going up and they are short that they may want to restrict online buying to ease buying pressure so that they can cover thier short positions. A couple weeks ago we bottomed again and two days later a couple brokerages restricted buying on normal volume and a normal rise.
Also, they may not be short at all. They may be trying to ease buying pressure so that they can accumulate shares for themselves at the discounted price without driving the price up. Then when they are done accumulating they let it run.
To me there are only two reasons to restrict buying either to cover short positions or to accumulate shares at a low price. They never restrict selling prssure when a stock is tanking.
News 
Market Data 
Discover 
AI
