So Theta for deep ITM puts may be positive as option approaches maturity - this makes sense as uncertainty on return gets lowered .what about for calls? Wouldn’t it be the same case?
For calls, time value is always positive. (There might be an exception for a stock that’s about to pay a dividend, but don’t worry about that.)
Still don’t conceptually understand why time value is positive. eg. For an in the money call option, the time to maturity still represents a risk factor. As it approaches maturity, the risk decreases.
Conceptually, I don’t see it being different from an in the money put?
As long as there is time left till expiration, there’s the possibility that that price of the underlying could increase and the value of the call option could increase. Note that the upside is unlimited, while the downside is limited; that’s why the time value is positive.
For a put option, the upside is limited; as the price of the underlying approaches zero, there’s more of a chance that it will increase than decrease because there’s nowhere to go down.
Great explanation - got it now, thx