Well said.....
"Although equity options literally (ie legally) expire on the third Saturday of the expiration month, a day reserved for brokerage firms and The Options Clearing Corporation to confirm customers' positions, the day expiring equity options last trade is the Friday before expiration, or the third Friday of the month. This is also generally (ie not always the case) the last day an investor may notify his brokerage firm of his intent to exercise an expiring equity call or put. If this third Friday happens to be an exchange holiday, then the last day of trading for expiring equity options is the day before, or the third Thursday of the month.
Check with your brokerage firm about its procedures and deadlines for instruction to exercise equity options."
For example....Ameritrade says that it requires a sell or
exercize by 12:00 on Friday.....I suspect that this is for
their convienance.....
" What is an options expiration?
All options expire on a certain date, called the expiration date. This can be up to nine months from the date the options are first listed for trading- (unless the contract is a LEAP).
It has been standard practice for US-listed options to automatically exercise all long equity options positions that are at least $0.05 in-the-money. Starting with the standard equity expiration on June 21, 2008 and effective for all equity expirations thereafter, all US-listed options that are $0.01 in-the-money, based on the "composite" or "consolidated" closing or last sale price reported by the Options Clearing Corporation (OCC) price vendors for underlying security prices on the final trading day prior to options expiration, will be automatically exercised.
To exercise equity options outside this parameter or to submit a request to decline an exercise of options within this parameter, please notify a TD AMERITRADE representative of your exercise instructions. Your request must be received by us before 4:30 p.m. ET on the last trading day for the options contracts.
If you do not have sufficient cash, positions, or buying power to cover any possible exercises or assignments, please notify us of your intention to wire the necessary funds by calling Client Services at 800-669-3900 or close your position before 12:00 p.m. ET. TD AMERITRADE may take forcible action to close out any position that your account cannot support at any time on the last trading day for options contracts."