According to PANews, Bitcoin Core developer Luke Dashjr has expressed concerns over the finality of Bitcoin transactions, stating that the widely accepted six-block confirmation rule is no longer applicable. He claims that transaction finalization now requires over a week, raising questions about Bitcoin's censorship resistance. Dashjr attributes this change to the increasing centralization of Bitcoin mining pools, suggesting that traditional standards are outdated. He attempted to update the six-block confirmation target in Bitcoin Knots, an alternative to Bitcoin Core, but his calculations indicated that achieving 95% security now requires over 800 blocks, equivalent to approximately 5.5 days, due to Antpool's significant share of the network's hash rate.
Data from HashRate Index shows that Antpool controls about 16.67% of Bitcoin's total hash rate, second to Foundry USA's 33.12%. Other major pools include F2Pool (8.87%), MARA Pool (6.06%), and SecPool (5.19%). However, Dashjr disputes these figures, claiming that several pools, such as Braiins and ViaBTC, act as proxies for Antpool, amplifying its influence. He also notes that many miners operate under centralized pools, unknowingly contributing to potential network reorganization. Industry experts share similar concerns, warning that the growing dominance of a few mining pools poses risks of potential censorship or even a 51% attack on Bitcoin. Bob Burnett, CEO of Barefoot Mining, stated that if a single entity controls a large portion of the network's hash rate, it could manipulate the blockchain by reorganizing transactions.
Meanwhile, not everyone agrees with the severity of the issue as described by Dashjr. Daniel Roberts, co-founder of Iris Energy Ltd, downplayed these concerns, arguing that Bitcoin's design allows it to self-regulate over time. Roberts added, "Bitcoin may not be perfect, and we should continue to try to improve it, but these kinds of issues are typically self-correcting or intentionally designed."