Rules, rules. It is a matter of YOUR intent with the IRS...as I see it anyway. Never been challenged. I write off at end of year (Dec 31st). When they (your broker) gets them off the books...their own matter not yours. As long as you follow through with the broker and they are in FACT written off...same-o, same-o.
Your intent was 'pure'...notified your broker that you wish to write off in 2014 and use the write off for 2014 tax purpose - when the broker does the action is of no concern. You do not "double dip" in 2015 if that is when the stock was actually taken off the books with your broker.
Be a square shooter. Write off is a one-time action and if all proceeds are accounted for accurately (besides the date), you should be in good order with the IRS. Your INTENT counts.
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