Age requirement for proprietary traders?

Is there an age minimum of 21 to become a proprietary trader? I worked with a prop firm in Canada which does not have this restriction but was told by a member of an American firm that you need to be 21 in order to obtain the Series 56 and trade through the CBOE.

Not sure about in the US or Canada, but here in the UK you need to be minimum of 18 (an adult basically). You dont need any special licenses to trade CBOT CME or any other U.S exchanges as a proprietary trader.

If you are managing outside money this is different and would need to be regulated.