and when he says:
Garlinghouse: "Bitcoin Is Controlled by China"
The Ripple CEO told the crowd, "A number of prominent people, even Steve Wozniak, has said that he sees a world where Bitcoin is the primary currency. I think that's absurd. I don't think that any major economy will allow that to happen. By the way, it doesn't make sense."
He continued by saying, "I'll tell you another story that is underreported, but worth paying attention to. Bitcoin is really controlled by China. There are four miners in China that control over 50% of Bitcoin"
"How do we know that China won't intervene? How many countries want to use a Chinese-controlled currency? It's just not going to happen."
I do not understand the technical aspect very well, but I believe they are pools where there are many people from several countries mining, or am I wrong?