In its review of the stocks in its actively-managed funds that moved more than 15% up or down for the week, ARK Investment reiterated its view that Tesla's Bitcoin (BTC-USD) move looks like a game changer.The move "seems to be legitimizing bitcoin as corporate cash," ARK says.Grayscale Bitcoin Investment Trust (GBTC) was up 20% after Tesla (TSLA) announced its investment in crypto.GBTC is the second-largest holding in the ARK Next Generation Internet ETF (ARKW) at 8.34M shares, valued at about $408M. That's up from about 7.31M shares held at the end of Q4, disclosed in ARK's 13-F filed Friday.The Tesla move "seems to have marked a cultural and institutional tipping point for Bitcoin," Yassine Elmandjra, ARK's cryptoasset analyst, said this week on a webinar.A big reason is that Tesla "is both a thriving company and hasn’t had any prior involvement with Bitcoin," he added.ARKW rose 6.6% this past week. The ARK Innovation