Final answer:
A stockholder's ownership percentage can increase or decrease depending on actions like new share issuance or stock buybacks. However, with certain types of stock dividends such as stock splits, the percentage ownership remains unchanged.
Step-by-step explanation:
The stockholder's ownership percentage in the stock of a corporation can increase or decrease depending on various factors including the issuing of new stocks, stock repurchases by the company, and stock dividends. When a company issues more shares, the existing stockholder's percentage of ownership decreases if they do not buy additional shares to maintain their proportion of ownership. Conversely, if the company buys back shares, the existing stockholder's ownership percentage increases. Furthermore, stock dividends can alter ownership percentage if they are issued in a manner that changes the total number of outstanding shares. However, if a stock dividend is provided in a way that maintains the total share count, like a stock split, then the ownership percentage for each shareholder will stay the same.