The world’s largest asset manager BlackRock just debuted a new advertisement proselytizing the virtues of Bitcoin, but rather than cheer on the Bitcoin ETF issuer for its efforts, Bitcoiners aren’t happy.

The video, which is housed on the iShares Bitcoin Trust (IBIT) ETF page on BlackRock’s website, spends three minutes walking viewers through the evolution of money and key fundamentals of Bitcoin. 

One of those fundamentals is Bitcoin’s 21 million fixed token supply. 

While the video explains the pros of Bitcoin’s fixed supply, a caption simultaneously cautions viewers with a disclaimer: “There is no guarantee Bitcoin’s 21 million supply cap will not be changed.” That’s a sore spot for Bitcoin maximalists, who hold Bitcoin’s fixed supply as a nearly sacred tenet that ensures the cryptocurrency’s status as “hard money.”

The caption remains for approximately five seconds, eventually fading away as the narrator elaborates on the benefits of a fixed supply, never addressing the potential change. Most crypto observers might have missed it if not for MicroStrategy founder and massive Bitcoin bull Michael Saylor sharing the video on his X account on Tuesday.

And despite being just a footnote in the video, crypto observers have now latched onto the disclaimer and raised alarms.

“This is the problem with tradfi,” Solana co-founder Anatoly Yakovenko commented on X, referring to traditional finance and Wall Street. “They see crypto as an investment into a thing external to them,” he posted. He then challenged both BlackRock and Saylor to commit to running their own full nodes—that is, the software that operates the Bitcoin network—and guarantee they would only ever support the fork that maintains a fixed 21 million supply.

“They need to become the decentralized network, not be investors of it,” Yakovenko said.

Part of the reason this has got Bitcoiners and other crypto users so worked up is because it isn’t the first time BlackRock has made such a disclaimer. The company included a note in its June 2023 ETF filing which indicated that “a hard fork could change the source code to the Bitcoin network, including the 21 million Bitcoin supply cap.”

Some of the more paranoid in crypto began speculating immediately that BlackRock might use its newfound power as one of the biggest Bitcoin holders in the world to influence changes to the network, including the BTC supply.

Commenting yesterday on the new ad, author and philosopher Steve Patterson said on X: “You really think your little fucking node running on a Raspberry Pi is going to prevent Blackrock from uncapping the supply of Bitcoin?”

Are these concerns unfounded? Probably, but it’s got the Bitcoin community talking, including Blockstream founder Adam Back and early dev Peter Todd (who HBO recently suggested could be Satoshi Nakamoto himself).

A hard fork would require a majority of the Bitcoin miners, or those producing blocks and verifying transactions, to agree on new supply mechanics—something most in crypto suspect will never happen. Still, Todd today reminded the community that it is technically possible. “Obviously, if the community agrees to change the 21 million limit they can,” he posted on X.

Nevertheless, Bitcoin stakeholders agreeing to change something as fundamental to Bitcoin’s core as its fixed supply would appear to run counter to the financial incentive that exists to maintain the status quo. So why would BlackRock continue to make it an issue?

Responding to criticism regarding the “silence” from Bitcoin OGs on BlackRock’s perceived misstep, Back said: “Obviously their lawyers made them write that as they sell investment products and they don’t have control.”