Here's a scenario I want to throw out there:
What if big institutional exchanges, either now or soon, decided to invest their profits into Bitcoin mining operations? Like, what if they gathered enough computing power to actually take control of a 51% hash rate in the network? Is it possible this is already happening?
With all the cash being raked in from block rewards these days, this thought has been on my mind a lot. Seems like a pretty wild topic to dive into, and I’m keen to hear what others think about it or any insights you might have.
Bro, this is not a trip to the store for oranges
First, ASICs need to be produced, Manufacturers have a huge backlog of orders.. You won't be able to buy a lot of equipment right now, you'll need to wait for the equipment to be produced.
Next, you need to install this equipment somewhere, and this requires huge mining capacities.
Mining companies won't shoot themselves in the foot, this is their business.
In theory, this is possible if you have your own ASIC production and huge factories for generating electricity, but you won't be able to produce the chips yourself.
Don't worry, it's unlikely to happen anytime soon, and a 51% attack won't steal coins from your wallet.
It would make people question Bitcoin's security and decentralization, where it would affect Bitcoin (and many altcoin) price negatively. I doubt they're willing to kill their own business that way. In case they split the hashrate into several pool and never perform any easily detectable attack (e.g. selfish mining), AFAIK they could do is intentionally exclude certain address/TX where it only delay how fast such TX getting confirmed.
No, although some people have concern about possibility of multiple mining pool work together.
Buying 51% is not a Costco run. Hashrate is hardware + cheap power + logistics. Exchanges have cash, but wafers and PSUs have lead times and siting takes months. Pooling other people's hashrate is easier, but then you are herding independent miners who can leave in a day.
What 51% can and cannot do:
Cannot change the rules or steal coins. Invalid blocks get orphaned by nodes.
- Can censor (leave out some tx), and with a true majority they can do it indefinitely while they keep that majority.
- Can double-spend targets by privately mining and reorging, mainly to defraud counterparties like exchanges. Mitigation is more confs and risk controls.
- Economics bite hard: visible censorship or reorgs nuke revenue and reputation; miners and users route around the attacker.
The real risk today -- Power over block templates lives at pools. A few large pools under the same policy pressure could soft-censor. That does not require 51%; it just slows some transactions and annoys everyone.
What helps in practice is:
Miners: prefer pools that commit to neutral templates and adopt Stratum v2 with job negotiation so miners, not pools, pick transactions. Be ready to switch pools.
Users/merchants: self-custody, run your own node, and choose sensible confirmation policies for incoming funds. Big payments get more confs.
Devs/operators: diversify funding, monitor pool shares, and keep pushing open standards that reduce single chokepoints.
Is this already unfolding? Exchanges dabble in mining and some run pools. That is a long way from coordinating a profitable majority attack. The more realistic failure mode is policy-driven filtering by a handful of pools, which market pressure has reversed before.
To put it briefly, any miner wants to make a profit, which depends on the price of bitcoin and the stability of the bitcoin blockchain.
And it is technically impossible to produce a lot of equipment to make a 51% attack.