This weekend sees the scheduled launch date of Bitcoin Core model 30 (v30) and an extremely contentious second in Bitcoin’s historical past.
Though studies of alleged plans for a tough fork have circulated within the run-up to this controversial software program launch, it’s technically potential — albeit extremely unlikely — that Bitcoin may expertise a blockchain break up.
Within the occasion of a shock chain fork, the position of spot alternate traded fund (ETF) sponsors in judging which chain will retain the bitcoin identify and its BTC ticker image is underreported and poorly understood.
Regulatory filings for US-based BTC spot ETFs reveal that their sponsors have the discretion to decide on which Bitcoin fork they regard because the legitimate one within the occasion of a tough fork.
This upends the standard observe of letting miners or node operators resolve, which often select the fork with probably the most processing energy because the legitimate Bitcoin chain.
The most important spot bitcoin ETFs. (Supply: ETF.com)
The facility to decide on which bitcoin is bitcoin
BlackRock’s $87 billion IBIT prospectus states unambiguously, “In the event of a hard fork of the Bitcoin Blockchain, the Sponsor shall determine which network shall constitute the Bitcoin network and which asset shall constitute bitcoin in accordance with the Trust Agreement.”
Elsewhere, Blackrock admits that it won’t even select the biggest BTC as the actual BTC. “There is no guarantee that the Sponsor will choose the network that is the most valuable fork,” its legal professionals disclaim.
Bitwise’s spot bitcoin ETF prospectus contains related language. “The sponsor will promptly make a good faith determination as to which digital asset network is regarded by the community as the Bitcoin network and which is the ‘forked’ network.”
“Unless an announcement is made informing investors that a fork will be supported, a newly-forked asset should be considered ineligible for inclusion in the Trust,” disclaims ARK Funding Administration.
Along with the discretion to decide on which blockchain is the actual Bitcoin, some spot ETF sponsors additionally reserve the correct to ignore the worth of a tough forked blockchain totally for the needs of the ETF holdings.
“With respect to any fork, airdrop or similar event, the sponsor will cause the trust to irrevocably abandon the incidental rights,” disclaim each ARK Funding Administration and Grayscale.
“The only digital asset to be held by the trust will be BTC” because the ETF sponsor defines BTC.
Intraday shopping for energy for the BTC they select
Within the case of ETFs, sponsors actively purchase and promote belongings on an alternate all through every buying and selling day.
With the intention to purchase and promote BTC, the sponsors should agree which asset is BTC. Highly effective, multi-billion greenback ETF sponsors will select, on a real-time foundation and with untold liquidity, which asset to buy for his or her ETFs throughout any chain fork state of affairs.
Any sharp observer with the persistence to learn regulatory filings has observed the discomforting actuality that spot ETF sponsors select with human discretion — not by mining hash energy or node depend — which fork of BTC is their actual BTC.
Spot ETF sponsors are a brand new echelon of energy, alongside BTC miners, with the privilege of figuring out which digital asset preserves the BTC ticker image and their large funding flows.
As a comparatively new set of entities with this energy — launched solely for the reason that Securities and Change Fee’s approval of spot ETFs in January 2024 — monetary establishments like Blackrock and Constancy maintain extraordinary energy over funding flows into the BTC that they choose as the actual BTC.
Might Bitcoin Core v30 truly trigger a sequence break up?
Core v30, if builders launch it on-time, will introduce three modifications to the conduct of Bitcoin nodes queueing up transactions for upcoming blocks.
For the primary time in over a decade, nodes will settle for BTC transactions into their mempool with a number of OP_RETURN outputs.
Second, the info dimension of those outputs might attain 100 kilobytes — 120,000% greater than their earlier 83 byte restrict.
Third, v30 software program will nerf the “datacarriersize=” operation of node operators who need to filter out these giant chunks of information.
Inside the datacarriersize/OP_RETURN change is hidden a change to what number of OP_RETURN outputs are allowed. Beforehand, it was 1. With the datacarriersize change, it is now as many because the person desires.
The technical justification for a number of OP_RETURNs now being normal is…
— Jimmy Tune (송재준) (@jimmysong) October 9, 2025
Importantly, none of those modifications have an effect on the Nakamoto Consensus guidelines of nodes accepting validly mined transactions.
Core v30 will solely create variations between the mempools of pending transactions — not chain suggestions — of node operators utilizing alternate software program shoppers like Knots, BTCD, or Core v29 and prior.
For that reason, the Bitcoin blockchain will nearly definitely not fork this weekend. Sarcastic jokes concerning the loss of life of BTC at this time are incomes laughter throughout social media.
Nonetheless, the approaching launch of v30 is a useful reminder concerning the energy of ETF sponsors if Bitcoin ever had been to arduous fork.
