With options it's possible to have the same symbol both as long as well as short in the account by specifying "Buy to open" and "Sell to open". I just wondered whether the same would make sense also in stock trading? I don't know any broker that allows this for stocks in an account, but one of course can do it by using 2 accounts. In which situations would it make sense to have this possibility of having a symbol both as long as well as short, usually opened at different times, in account/portfolio? Of course the question is: why keep both if they eliminate each other? (Like matter and anti-matter )
You should never by choice carry long/short the same option overnight. It might subject you to early assignment on the short side and both are carried in the same account type (Type 2 Margin) while a long/short stock position will be in two account types (Type 2 Margin for the long and Type 3 short for the short). This question has been asked in the past several times. Unless your country has some type of tax code where you do not want to realize a profit or loss, I do not get where you see any advantage to this, and it will double your fees because you must exit twice.
You keep on asking the same thing again and again. The same answer remains. It makes absolutely zero sense to hold a long and short position in the same stock at the same time. Absolutely no benefit. Which part is STILL unclear?
I think it very well makes sense, even beyond tax issues, maybe in some very advanced scenarios/constructs, though I haven't figured out yet. Best indicator for this line of thought is: why is it allowed in options trading then?...
I have been in the business since 1981 and can't think of one good reason to be Long/Short the same exact Security or Derivative, which in essence makes you flat, no way to profit, vs closing the position. And it is possible that regulators do not allow boxed positions. I know the CME does not allow it. Too hard to monitor open interest. And there are scenarios where you can lose money but not profit.
Robert, I think it can best be used for spread-like scenarios. Ie. it's not flat; profit is very well possible!... And: have you never wondered why it has been made possible with derivatives?
Other than trying to dodge taxes as @RobertMorse stated, I can see one other purpose for simultaneously holding a stock both long and short. If a stock has very few shares available to short, and you expect a major announcement, after market close, that could drastically move the stock price (such as earnings or an FDA drug approval/rejection), it could be beneficial to have shares long that could be sold instead of trying to borrow shares to short. This is a way to play the announcement with the only risk being trading commissions if there is no price movement.