Mark .... there a couple of things that go on in the background...

Mark .... there a couple of things that go on in the background with options ... apart from the buying and selling parties

Because for example the NASDAQ is quote driven (not order driven like ASX), there are "market makers (MM)" that deal in the stock. These MMs need to pay real close attention to options. Those heavily shorted stocks (like Gamestop) have had huge call option buying (the right to buy the stock in the future at strike price). MMs - who are typically delta-hedging their option positions - are driven to trade substantial amounts of underlying shares or futures, simply because of the price of the underlying security changing, not as a result of news and without regard to the liquidity (inventory of stock) available to the MMs (so buy at the Bid) - the MMs must have inventory to deliver to actual stock buyers and so buy the stock to have available for sale ... which creates even more demand which sends the price up further (self fulfilling feedback loop).

Option "Delta" refers to the % of an outright long/short position the option is risk-equivalent to (and probability of option expiring ITM).

"Gamma" is effectively the movement in the option from OTM to ITM and can cause volatility and "overreactions" and boy has that ever happened in Gamestop.

Could it happen over here ... of course ... take a look at @lesv link on shorted stocks by Shortman for candidates

But there is a difference ... Melvin and Maplelane are shorting not simply because they think the share price is "too high" but because the business is doomed (going to $0) ... and I think they are correct in their assessment of Gamestop. Plus they are only small Hedge Funds (yes a couple of Billion is small).

Don't see PLL having anything to be concerned with ... but anythings possible. We're in the bowels of market structure now though.