From the perspective of Elliott's Wave Theory:
It broke the trend line, went up the 1 as indicated by line red (which I mapped out a two days ago) and it's starting to pull back into .5-.618 feb territory. Watch this ARK carefully. It is looking extremely bullish and like it will blow up anytime soon.
RSI also indicates overbought and MACD look like they are...
The chart looks like it is breaking out of a downtrend (starting an Elliott's Wave pattern )and flirting with the long term resistance entering 2018 with a vengeance.
The ultra high (70+) RSI and closing MACD is indicative of a reversal typically between back to 0.5 fib to 0.618 fib of wave 1 as indicated in the chart above. And having a strong run into the third...
