Bitcoin is known as a censorship-resistant network. This characteristic is usually presented as one of its basic selling points. The Bitcoin development community is stirred up with intense debate over the impending removal of spam filters that limit non-monetary data to 83 bytes per block. Opponents have allowed on-chain posting of child porn, claiming that Bitcoin effectively makes it illegal in most jurisdictions.
summary
- Spam Wars is intensifying. More and more people are switching from Bitcoin Core to Bitcoin Knot, warning that the Bitcoin Blockchain could turn into a child porn home.
- The CP issue was raised several years ago before a streamlined plan to remove spam filters, so the issue was rejected at the time.
- Advocates of the change cite new capabilities as a reason to implement the V30. New opportunities open up. People can store new types of data on-chain, but their opponents can use different versions of Bitcoin Core or other node software.
Bitcoin Core and Bitcoin Knot
Blockchain data is monitored and verified by nodes. Each block may contain up to 83 bytes of non-monetary data (for example, images). This opportunity is possible via the op_return script. Some call it a spam filter because they believe that Bitcoin Network (BTC) will help them to be used accurately for currency trading. OP_Return prevents your network from overflowing with arbitrary data (non-financial data). Spam filter removal opponents say the change could cause network congestion.
However, some developers have advocated for eliminating spam filters, increasing arbitrary data limits to about 2 megabytes per block. The reason for this change cited by these developers is to dismantle restrictions and censorship. Open gates for various use cases, such as sharing JPEG files, videos, documents, and more.
I really hate politics.
Therefore, I have little patience with those who try to impose the traditional governance model on Bitcoin.
If you don't like Anarchy, you're free to leave.
– Jameson Race (@lopp) August 26, 2025
A more technical excuse is that images and other non-monetary data are already on the Bitcoin blockchain. Such data is posted as transactional output forever, causing the blockchain to bloate and slow the transaction speed. The proposal aimed at removing any data restrictions was introduced earlier this year by Peter Todd.
Bitcoin Meditation Series
1.
Satoshi asked Core & Knot:
My kids, how does Bitcoin last forever?Core said: by becoming a lot!
The knot said: by refusing to become something else… pic.twitter.com/fdfssmoror
-Zatoichi🌊 (@Zatoichi42) August 24, 2025
Advocates for the removal of spam filters are the community behind Bitcoin Core software, the oldest and most popular node program. As they achieved the consensus, Bitcoin Core Version 30, which increases the Op_return space across blocks, is scheduled to be released in October 2025. After the October update, the Bitcoin Network will probably get any data, given that the majority of the blocks have been verified using Bitcoin Core software. Those who oppose filter removers use Bitcoin Knot nodes mostly.
Comment on whether this process is “hurried.”
As someone who has written and merged Mempool's policy changes over the past four years, I think this is a par for the course.
-The original PR was discussed about two years ago (of course reflects the discussion that took place in 10 years…
– Gloria (@glozow) June 9, 2025
The debate continues, with many people using Bitcoin Core deciding to move to Bitcoin Knot, but the removal of the spam filter was approved and scheduled in October 2025. Advocates of Spam Filter Removal can use older versions of the software or switch to another if they're not happy with the update.
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The fallout in discussion has become personal and quite aggressive. At one point, a personal attack on X caused Gloria Zhao, one of the leading Bitcoin core developers, to temporarily delete his account. Some critics accused Bitcoin Core developers of serving the benefits of Citrea, the zero knowledge layer 2 rollup protocol, allowing Ethereum-like features to be used on the Bitcoin blockchain. The Bitcoin mechanic, one of the bitcoin developments, claims he was blocked on GitHub after criticising the Bitcoin Core plan.
Those seeking major changes in Bitcoin are partnering with companies whose current use of Bitcoin is the motivation behind the change.
Pointing this out in the GitHub discussion banned me. https://t.co/vaanbybe5o pic.twitter.com/5yyxgtwati
– Mechanic #fixthefilters #300kb (@grassfedbitcoin) April 28, 2025
The reason for such a tough pushback to Peter Todd's proposal is because Bitcoin Core is a highly influential software. At the time the proposal was made, I was responsible for about 99% of all Bitcoin blockchain data. As the conflict continues, more than 15% of the Bitcoin Core community have opted out of becoming Bitcoin Knot Runners.
Concerns about illegal content
It was a Bitcoin mechanic who rekindled the debate on August 31, when he posted an hour-long video on his YouTube channel and X, the video claimed that deleting the spam filter would elicit “unexpected results.” Bitcoin's core supporters cite other blockchains without spam filters as evidence that child pornography does not penetrate the blockchain.
Given the immutable and censorship resistant Bitcoin ledger, it means that illegal content will stick there forever and Bitcoin will turn into storage for illegal content. Unlike financial data, whether they are involved in the sale of illegal things or not, according to Bitcoin mechanics, any data itself may turn out to be “something you just discriminate against, depending on what is included.”
Bitcoin mechanics have admitted that “unpleasant content” had already been uploaded to the Bitcoin blockchain in 2013. There is an inscription shape. However, he says that the current structure allows Bitcoiner to avoid connecting with this data by not using inscriptions. In contrast, potentially illegal content that can be uploaded after a Bitcoin Core update will become available rather than in hexadecimal format.
“Why would someone want to store their children's PR0N on the blockchain?”
Because having others store it for you is much more desirable than storing it or hosting it yourself. Especially when the storage medium is widely distributed among morally defensible people…
– Mechanic #fixthefilters #300kb (@grassfedbitcoin) August 31, 2025
The topics of Bitcoin and child pornography are nothing new. It was widely covered in 2017. At the time, spam filters were working so well that vigilantes had to admit that they were incorrect. However, today there is another problem with the increase in data per block. They say that countries and countries may prefer to ban Bitcoin entirely, as running a node equals storing illegal content on a computer. Legally, this concern requires expert research, but morally, some people in the Bitcoin community are already considered unacceptable.
Core pretends that this video didn't appear.
Due to changes in Core, Bitcoin is at risk of being misused to store illegal materials (such as CP).
This gives the government the perfect excuse to ban Bitcoin or make nodes illegal.
Core Development @glozow –
Your choice will determine whether…https://t.co/ptmgabnddw– Joyce (@bitcoinwifey) September 1, 2025
This system is decentralized and community-driven, so this kind of heated battle is nothing new to the Bitcoin space. History has already seen conflicts over the inclusion of block size and ordinal numbers. With the imminent core update for Bitcoin, you can see how big the problem will be in the next few months.
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