O'Reilly Automotive Inc. said Friday that it will increase the number of shares it may buy back.
The company's board approved buying back up to an extra $500 million worth of shares, raising the total pool for its buyback program to $2 billion. The authorization for the additional shares will last for three years.
O'Reilly isn't obligated to buy back the shares and could change its mind if it decides that buying the shares wouldn't be a good deal.
The company didn't say why it is increasing its possible stock buybacks. However, companies usually portray buybacks as a favor to shareholders: If a company buys back its own shares, it should decrease the number of shares in circulation and boost earnings per share.
Critics say that companies would serve shareholders better if they spent the money reinvesting in the company, or returned it to shareholders in dividends. They also argue that companies don't often reduce their total number of shares for long, since they tend to issues shares to pay employees.
O'Reilly Automotive, based in Missouri, sells car parts and accessories. The company's shares fell nearly 3 percent Friday amid broad declines in stocks.