What forex brokers do billionaires use

hi,
What forex brokers do billionaires use like george soros? any suggestions?

I assume George Soros and the like are treated the same as hedge funds and receive prime brokerage services from Investment Banks.

They use the actual Foreign Exchange.

They are "On Exchange" Similar to how an ECN works. The trades are blind,
(meaning if someone) sell 2 bn cable, the buyer does not know who the seller is.

Foreign Exchange players consist of
Central Banks,
Countries
Broker Dealers - Like your market maker
Hedge Funds
Investment Bank/ Funds
Other Banks - JPM - Deutsche Bank, Citibank
Extremely Wealthy Individuals - ie; George Soros.

Large Companies - For instance the Hostile Takeover of Cadbury LDN by Kraft USA
Kraft Likely needed to Buy Cable for this sale, thus their bank went on the Exchange and bought xxx lots cable. -- Remember the Pound strength around this sale??