you need to be an owner until the ex-date to get the dividends, meaning you must still have the shares until after the market opens on the ex-date. but after the market opens on the ex-date, you can sell and still have the dividends.
"However if I purchase the stock again on Dec 8, I technically own the stock on the Date of Record, but I do not qualify for the dividend because the record of ownership for the second purchase is Dec 10th, two days after I purchased the stock."
Yep you got it though I would clarify that you PURCHASED the stock on dec 8th but do not OWN those shares until dec 10th. Your first purchase gets you the dividend. Your second does not. The distinction between purchase and ownership is important for more than just dividends. Voting rights, class action lawsuits are two others that go by ownership.
people. ignore the record date. you don't need to know that. all you need to know is that you keep the dividend so long as you buy the stock before the ex-date and hold it until the ex-date, meaning you cannot sell until the ex-date.