Last trading day
The last trading day is the final day on which an order to buy or sell an options contract or futures contract can be executed.
In the case of an options contract, for example, the last trading day is usually the Friday before the third Saturday of the month in which the option expires, though a brokerage firm may set an earlier deadline for receiving orders.
If you don't act on an option you own before the final trading day, the option may simply expire, or if it is in-the-money it may be automatically executed on your behalf by your brokerage firm or the Options Clearing Corporation (OCC) unless you request that it not be.
But if a futures contract isn't offset, the contract seller is obligated to deliver the physical commodity or cash settlement to the contract buyer.
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