Actually, quite easily...
Corporate distributions are payments made by the corporation to its shareholders. Dividend payouts follow a set procedure. Board members approve a dividend on a declaration date and investors, as of the ex-dividend date ("holder-of-record" - you own shares as of the date dividend recipients are recorded), will receive payment on the payment date.
In other words, did you or any other shareholder of the company receive a payment from the company that wasn't part of a regular paycheck or bonus? If yes, then your company probably made a dividend payment.
In the event your company does not have sufficient accumulated earnings, the payment made by the corporation could be considered a return of capital instead of a dividend. If this is the case, the payment would go to reducing your basis in the company rather than being taxed as income.