Bitcoin mining pool Ocean has come under attention due to a transaction review allegation. Developer Kruw accused a miner of excluding his transaction in block 973,817, resulting in transaction fees being 7.68% lower than the expected template.

According to Kruw, the miner Ocean rejected his merger transaction.

• Kruw accuses Ocean, a miner, of excluding his merge transaction in Bitcoin block 973,817.
• The comparison he shared shows that the transaction fees are 7.68% lower than expected for the block template.
• Coinjoined Chris defends miners' right to make autonomous choices regarding transactions through Ocean's DATUM.
• Kruw believes that mining pools should not accept work that deliberately sacrifices the transaction fee income of participants.

Kruw initiated this debate on X on October 30th, sharing a block comparison chart and requesting Coinjoined Chris from Ocean to get involved. Subsequently, the two parties argued over whether mining pools should forcibly charge a handling fee when individual miners decide which transactions to include.

Chris indicates that he supports CoinJoin and also hopes that miners receive economically attractive transaction fees, but he opposes controlling miners' choices through pool payments.

Block comparison leads to investigation and accusations

In the original post, Kruw referred to this miner as “Powre” and described the excluded transfer as his merge transaction.

He wrote: "My merge transaction was reviewed by miner ‘Powre’ with the username ‘OCEAN’ in block 973,817."

The comparison chart he attached shows that the expected block contained 3,580 transactions, while the actual block only had 1,698. The block weight shown in the chart decreased from approximately 3.99 million weight units to 2.93 million, and the rounded transaction fees were 0.017 BTC and 0.016 BTC respectively.

The comparison of handling fees shows a difference of 7.68%. Kruw believes that the uncollected handling fees have harmed the interests of other participants in the mining pool, and claims that the block has been “partially emptied.”

His accusations are directed at the income from transaction fees. The percentages shown in the chart do not represent a measure of the total block rewards, nor do they indicate that each participant's earnings have decreased by 7.68%.

The transaction fee highlighted in the screenshot is 223聪, with a displayed rate of 0.15聪 per virtual byte. The comparison chart labels it as a merged transaction and shows that it was first observed 4 minutes before the block was generated.

Although the discussion mentioned CoinJoin and financial privacy on multiple occasions, the original post by Kruw clearly labeled this transfer as a merger transaction.

Ocean's DATUM defends miners' right to choose

In response to this complaint, Chris stated that the DATUM settings of Ocean allow miners to construct block templates on their own. Some miners prefer to choose the highest transaction fees available, while others adopt their own transaction filtering policies.

He defended this right to make decisions, even though he did not agree with the final outcome.

Chris writes: 'I am a firm supporter of CoinJoin. I believe that financial privacy is the foundation of Bitcoin, and we should do everything possible to promote this.'

He agrees that not charging transaction fees is economically debatable, especially when this income can benefit the participants of the Ocean payment system TIDES.

However, Chris suggests that mining pools should not decide which valid transactions individual miners must include. He believes that imposing a transaction selection policy at the mining pool level would weaken the control that DATUM grants to miners.

In a subsequent reply, he directly addressed the issue of payment.

“TIDES will reward the computing power contributed according to our payment rules, rather than depending on whether OCEAN approves of a miner's transaction choices.”

Chris indicates that he hopes the block will contain more CoinJoin, PayJoin, and anchor transactions. What he opposes is allowing mining pools to enforce these preferences through payment decisions.

Kruw believes that the payment mechanism can enforce the collection of fees.

Kruw refuses to distinguish between transaction selection and pool control, believing that Ocean can reject those jobs with fees below their acceptable standards.

He suggested that mining pools could respond to templates with lower transaction fees with “Rejected share check mempool connectivity”, instead of paying rewards to miners.

The rejection mechanism he proposed is one of his arguments regarding how Ocean should handle this matter.

Chris questions whether there is a standard for the total "correct" transaction fee that is recognized by everyone. He says that different nodes receive transactions at different times, may adopt different forwarding strategies, or may see transactions that other miners have never seen before.

He wrote, "A block transaction fee that is 7.68% lower than the maximum value assumed in a certain scenario does not in itself prove the existence of censorship."

He also questioned who should set the acceptable thresholds, citing 99% and 95% as examples. At the same time, he pointed out how mining pools handle private transactions, propagation delays, and the reasonable differences between different mempool.

When Chris describes this practice as refusing to honor a valid job and withholding payments, Kruw clearly expresses support for this approach based on centralized profitability checks.

He replied, "The only purpose of allowing miners to create their own templates is to enable them to access additional profits that the central authority might overlook."