Institutional market maker Wintermute's analysts state that despite the altcoin index rising 5.0% in week 39, outpacing Bitcoin's 4.1% gain, retail investors' optimism is premature. The outlook for XRP and other altcoins now depends on whether Bitcoin can hold its newly gained ground after its first weekly close above its 50-week moving average since last November. Wintermute cautions that if Bitcoin fails to hold the $82,500 level, altcoin rallies could stall. The firm expects this level to be retested multiple times.