taxes don’t really have a season on wall street—and a host of stocks that have been on the losing side will be sold from now through the end of the year to trim bills from the irs it’s called taxloss selling or “harvesting” and here’s how it works a portfolio manager sells an investment at a loss to offset the gains from other assets a stock sold for a gain is taxed but one sold at a loss isn’t so incurring losses is how the portfolio manager lowers the overall amount of gains—and shrinks the portfolio’s tax bill