Never heard of them.
Were they a fiat sportsbook and recently started taking bitcoin as a way to deposit to the players accounts?
It seems like this is the way all sportsbooks are taking their customer bets now.
Intertops accepted the world’s first ever online sports bet and that shows directly that they are longest online bookmaker.
Intertops is a big player in the US market and has a great reputation in US. Also they accept bitcoin for more than a year now.
https://bitcointalksearch.org/topic/intertops-one-of-the-globes-largest-sites-for-sports-bet-now-accept-bitcoin-2006519
Intertops had a skin on the Revolution Gaming Network scam, where Lock Poker, Juicy Stakes and Win Cake stiffed players for over $15 million!
Intertops then formed a relationship with the Juicy Stakes scammers: http://forumserver.twoplustwo.com/showpost.php?p=46655656&postcount=1
There are several withdrawal issues reported after relationship with Intertops: http://forumserver.twoplustwo.com/29/news-views-gossip/juicy-stakes-holding-my-300k-hostage-1451147/
Later, the Win Cake scam was transferred to the Juicy Stakes scam, where players lost 90% of their account balance: Win Cake Poker + Juicy Stakes