Care to elaborate? Note that I'm not a "tax advisor", accountant, etc! However, in the most simplest form, you realize a loss "when the stock is sold".
I know you can complicate things by declaring, proving when a stock became "worthless"; re-filing returns if needed, etc, but the original question from the poster was "how do I claim the loss"? Not "what are my options".
What could be easier than "selling" the shares to your broker? If they give you a penny, the shares were not worthless, right? Why would it matter "when" they became "almost" worthless? The "loss" will automatically appear on your year end statement/1099 you receive from your broker.
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