I didn't know there was a mechanical aspect to this.I didn't say they don't go up but even if it's up the share price reflects the dividend deduction.
From the article:
With dividends, the stock price typically undergoes a single adjustment by the amount of the dividend. The stock price drops by the amount of the dividend on the ex-dividend date.1 Remember, the ex-dividend date is the day before the record date. If investors want to receive a stock's dividend, they have to buy shares of stock before the ex-dividend date. The record date is the date the company determines who are shareholders who receive dividends. (The ex-dividend date is before the record date to allow transactions of the trade to settle before the record date.)
For example, suppose a stock trading for $50 per share declares a $0.50 dividend. On the ex-dividend date, the price adjusts to $49.50 ($50 minus the $0.50 dividend) for each share as of the record date. And that's it—no changes to the listed options strike prices or contract terms.
But if the market can, and often does, override that Div payment reduction, then it doesn't matter. This from Investopedia:
The declaration of a dividend naturally encourages investors to purchase stock. Because investors know that they will receive a dividend if they purchase the stock before the ex-dividend date, they are willing to pay a premium.
This causes the price of a stock to increase in the days leading up to the ex-dividend date. In general, the increase is about equal to the amount of the dividend, but the actual price change is based on market activity and not determined by any governing entity.
On the ex-date, investors may drive down the stock price by the amount of the dividend to account for the fact that new investors are not eligible to receive dividends and are therefore unwilling to pay a premium.2
However, if the market is particularly optimistic about the stock leading up to the ex-dividend date, the price increase this creates may be larger than the actual dividend amount, resulting in a net increase despite the automatic reduction. If the dividend is small, the reduction may even go unnoticed due to the back and forth of normal trading.
Many people invest in certain stocks at certain times solely to collect dividend payments. Some investors purchase shares just before the ex-dividend date and then sell them again right after the date of record—a tactic that can result in a tidy profit if it is done correctly.