Bloomberg ETF analyst Eric Balchunas didn't mince his words when contextualizing how impressive he finds the early performance of BlackRock's spot bitcoin ETF. 

BlackRock's ETF "ended up with 414 reported holders in its first 13F season, which is mind boggling, blows away record," Balchunas posted to X on Thursday. "Even having 20 holders as a newborn is bfd, highly rare."

For a month and a half, 13F filings for financial institutions — those required to report their holdings as of the end of the first quarter of 2024 — have been trickling in, providing insight into which organizations bought spot bitcoin ETF shares and exactly how much each purchased.

BlackRock's ETF, ticker symbol IBIT, has been the most popular in terms of growth, swelling from zero dollars in assets under …