Bitcoin Forum

Hi everybody,

I have a question. Just out of my curiousity  ??? :)

Independently of ethical aspects and the blockchain philosophy, could miners freeze (or block) an address by ignoring its transactions?
For example, suppose an ICO is confirmed to be a scam. The raised money is in a sense lost forever from the investors' standpoint.
But, could miners block the funds so that scammers cannot use them by ignoring any request to send funds from the scam address to a personal address?
I know miners can ignore a low fee transaction. So it seems technically possible.
I repeat, I don't want to start a discussion on ethical issues and how this goes against the philosophy of decentralized economy where nobody can control others.
Mine is just a technical question.

Miners have all the rights to control what goes in and what does not go into their block. They can definitely choose to exclude any transaction[1] with a relatively simple change.

In reality, its impossible to convince miners for refusing to mine it at all. They can even potentially offer a bounty for it to mine and convince 51% of the miners to help them.
[1] http://codepad.org/7RQZIkhd

That makes sense. Thank you.

If miners totaling more than 50% of the global hash power all agreed to reject the transactions AND all agreed to reject any block that includes the transactions, then yes.  That would be considered a majority attack (also called a 51% attack) whereby the cartel of miners are manipulating the blockchain to control which blocks are included.

If less than 50% of the global hash power agreed to engage in the attack, then they would not succeed. The person creating the transactions could obtain enough hash power to mine a block themselves, or they could convince a small mining operation to do it for them.