It might seem like a simple question, but the more you look into it, the trickier it gets. (I believe coinmarketcap had a criteria/screen for this earlier and XRP was the only one in the top 10 that show up as pre-mined. ) Since the valuation of all the alt-coins are set by supply and demand, knowing if and how it is premined or owned by the creators from the start is very interesting.
To do your own research and due diligence is complicated. I welcome you to comment below and post links to good screening tools that shows good info regarding this.
Comment below