The U.S. Securities and Exchange Commission finally has approved spot bitcoin (BTC-USD) exchange-traded funds on Wednesday, bucking a long string of denials for such a product that has spanned many years.

SEC Commissioner Hester Peirce favored the approval, saying she commends "applicants’ decade-long persistence in the face of the Commission’s obstruction."

She noted the regulator should have been comfortable with greenlighting spot bitcoin ETFs in the past, as other bitcoin-based products have been trading on regulated U.S. exchanges for years.

"Instead, until today, the Commission remained steadfast in its unwillingness to let spot bitcoin ETPs into US markets," she said in a statement.

Commissioner Mark Uyeda, though also concurring with the approval of the ETF applications, laid out three concerns he has with respect to the SEC's approval order:

1. "The Approval Order improperly attempts to validate the application of the “significant size” test to spot bitcoin ETPs that was struck down by judicial review.
2. The Approval Order invents a novel, previously unarticulated standard to form the basis for approval.
3. The Approval Order disguises the Commission’s motivation for accelerating the approval of the applications, which is to prevent a first-mover advantage among spot bitcoin ETPs."

Caroline Crenshaw, a fellow commissioner at the SEC, dissented from the approval order, calling the commission's actions "unsound and ahistorical.

Such actions "put us on a wayward path that could further sacrifice investor protection," she said in a statement. "I cannot agree that these actions serve either our statutory or foundational investor protection mandates."