Timo is the sole owner of Jazz Inc., an S corporation.  On October 31, 2020, Timo executed an unsecured demand promissory note of $15,000 and transferred the note to Jazz (Jazz could require Timo to pay it $15,000 on demand).  When Timo transferred the note to Jazz, his tax basis in his Jazz stock was zero. On January 31, 2021, Timo paid the $15,000 to Jazz as required by the promissory note.  For the taxable year ending December 31, 2020, Jazz incurred a business loss of $12,000.  How much of the loss clears the stock and debt basis hurdles for deductibility?