(1) What happens if I buy a stock before it splits? For example, I buy 100 shares of A at $10 dollars per share a day before a 2:1 split. With T+2, delivery will be after the stock split. Does the seller deliver 100 old shares of A at $100 each to me or 200 new shares of A at $50 each?
(2) Let's say I sell 100 shares of stock A to Bob on Day 1. A few hours later, I borrow 100 shares of stock A from Alice in order to deliver to Bob. This is known as naked short selling (I short-sell stocks before borrowing them).
According to regulations, I have to deliver the shares to Bob on Day 3. Coincidentally, Alice delivers the borrowed shares to me on Day 3 as well. I'm not entirely sure how long it takes for me to transfer shares to Bob. Do I have enough time to receive these shares and deliver them to Bob in turn within the same day or will I fail to deliver them to Bob in time?
(3) Is it possible to exploit arbitrage in dark pools? I know that prices in dark pools can be different from the public price so is it possible to buy stock A for $100.00 on a dark pool and sell for $100.10 on another dark pool?