Dealer hedging is not quite this simple. Market makers will hedge their gamma exposure by doing whatever it takes to be delta neutral. So lets say you buy an ATM call from them with a delta of .5, that gives them a net delta of -50. If they are able to sell a put with a delta of -0.5 they would then be delta neutral, however, if there isn't someone to sell to (they are the ones making the market, after all), they will have to hedge by buying 50 shares of the underlying. These dealers are constantly trading high volumes of options across many strikes and expiry dates. They have algorithms that will tally up the net delta of everything on their books and buy or sell shares to get them back to neutral both when the price changes and when they buy or sell options. Since retail investors typically will sell calls to buy puts (insurance) and market makers are usually the ones taking the other side of this trade, these dealers are generally always Long delta, and thus need to Sell shares to hedge. Dealer gamma hedging will typically compress market volatility and keep prices from rising or falling too drastically. My knowledge on this subject is pretty basic (I've never actually talked to a market maker) This site goes into more detail: https://spotgamma.com/ Regardless, I agree with you that this article is BS and oversimplifies how market makers manage their books. Unless these reddit guys are absolute whales they wouldn't be able to move a stock like this. It's most likely short covering causing these moves.1) When you buy a put, someone sells a call. Nobody has to actually buy any shares. The argument of Bloomberg here is that a bunch of pseudonymous nerds are forcing dealers to buy stock on public markets through options contracts, which if that were the case, wouldn't be called "options." You can let an option expire - that's why they're so cheap.