According to the data from Lookonchain, 9 ETFs added 4,135 $BTC (+$290 million) on May 21. Grayscale added 436 $BTC (+$30.58 million) and currently holds 289,390 $BTC ($20.3 billion). Blackrock added 957 $BTC (+$67 million) and currently holds 277,716 $BTC ($19.48 billion).