1314 GMT - Bitcoin's rise is partly due to massive accumulation by so-called mega-whales, XS.com's Simon-Peter Massabni says. The major investors, who each hold more than 10,000 bitcoin, added more than 30,000 bitcoin Thursday, according to figures from BGeometrics, Massabni says. "Bitcoin's continued upward trend comes alongside liquidity flowing at an accelerated pace into the cryptocurrency market through various channels," the analyst adds. There has also been a boost from optimism about regulatory factors in the U.S., XS.com says. A rapid return of speculative liquidity to cryptocurrency futures is also supporting bitcoin. Bitcoin is up 5.7% at $77,148.10, according to LSEG data.