How do I report a loss due to reverse stock split that has not been reported to IRS, and hence not on form 1099-B?
You report it as a sale of stock with the cash in lieu being the "proceeds" of that sale. If you really didn't get a 1099-B then use the "Stocks, Mutual Funds, Bonds, Other" interview and tell TurboTax that no 1099-B was received.
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