Here is the story behind recent bitcoin bull run. Apparently, we have someone very rich who bought $344 million worth at an average of $8400 from 9 to 12 February.
Meanwhile, noted cryptocurrency analyst Tom Lee, who has a $25,000 price target for bitcoin by the end of this year, has predicted a bump in its prices starting in July
And this mysterious buyer doubled down on bitcoin by purchasing even more BTC. 41,000 coins this time, just before its price hit $10,000.

More info here: https://www.investopedia.com/news/bitcoin-price-retreats-10k-mysterious-buyer-emerges/