Odaily News According to the data of US spot Bitcoin ETF monitored by Lookonchain on May 15: 1. Grayscale GBTC reduced its holdings of 12 bitcoins, worth approximately US$763,000; 2. Grayscale currently holds a total of 289,337 bitcoins, worth approximately US$18.61 billion; 3. Ark21Shares increased its holdings of 2,164 bitcoins, worth approximately US$139.2 million, and currently holds a total of 45,705 bitcoins, worth approximately US$2.94 billion; 4. 9 Bitcoin ETFs increased their holdings of a total of 2,106 bitcoins, worth approximately US$135.46 million.