The dividend reinvestment basis calculates the cost basis, market value, and capital gains (losses) for plans, automatically adjusting for stock splits. For shares that are received in lieu of cash, you’re holding period begins on the day after the date of the dividend reinvestment basis. If you make an optional purchase through a dividend reinvestment basis, your holding period begins on the day after the date the plan makes the purchase (not the day you send in your money). These rules are in keeping with the general rule for stock purchases: the holding period begins on the day after the trade date of your current holdings or initial dividend reinvestment basis purchase.