There is a very easy way to verify not only the licence of a broker, but the complains´s history of the broker, which is way more important.
You just go to the bottom of the page on the website of the broker, there got to be, there must by law be the regulator and its licence number, if not, get away from there fast, checking if you`still have your wallet or virginity, well the second maybe not, but anyway. The next thing to do is to get the number and name of the regulator(s) and call or email (better call) those regulators, saying something like: Hi, You know I want to invest in this broker and I want you to tell me if this is a broker regulated by you and if it is, the historical complains this broker had received in your organisation.
Now, if you call you do not need to eat nails or lose your hair, but if you emailed them... Seat tight and wait.
Sadly, many people think about this too late, when they already had invested money in the broker they are trying to check.
Another thing that I think helps a lot, is to trade with brokers which work by this two major figures:
ECN markets deals.
I hope this information is useful to you guys, I work for HYCM, a broker with 40 years on the field and my experience is around 10 years on the market and yes we have all of that.
Happy and secure trade guys!