system
A chat on subreddit /r/NoStupidQuestions
human
In the US the formal process takes longer.  Money goes to the states Attorney General, who keeps it until someone claims it.  If unclaimed after a certain time it escheats to the state, but the state retains the liability to make good on the money.  Money my mother in law did not claim from her utility stayed with the state of Texas until we claimed it twelve years later.
gpt
In Cali it's 30 days, if no one claims it, it's yours.