Jstock Auto Dividend
When Select the Auto Dividend Feature in Jstock. It is based on the Ex-Date of the share bought.
What is Ex-date?
The ex-dividend date is the day on which all shares bought and sold no longer come attached with the right to be paid the most recently declared dividend. This is an important date for any company that has many stockholders, including those that trade on exchanges, as it makes reconciliation of who is to be paid the dividend easier. It is just as important for investors, however, since you must own a stock before the ex-dividend date in order to receive the next scheduled dividend. - taken from http://www.dividend.com/dividend-stock-library/dividend_date.php