Players can verify the legitimacy of an online casino's license by checking for the licensing authority's logo displayed on the casino's website, which is typically found in the footer. They should then visit the official website of the licensing authority, such as the UK Gambling Commission, Malta Gaming Authority, or others, to confirm that the casino is listed as a licensed operator. Additionally, players can look for reviews and player feedback on forums and independent review sites to gather more information about the casino’s reputation and compliance with regulations. Always ensuring that the license is valid and up to date helps ensure a safer gaming experience.