51% attack does not correlate at all with owning 51% of the coins, it is about having 51% of the network hashrate. If you were to round up the current network h

51% attack does not correlate at all with owning 51% of the coins, it is about having 51% of the network hashrate. If you were to round up the current network hashrate from 145 million TH/s to 150 million TH/s, and use the Nicehash price of ~$219 per PH per hour as a price, it would cost around $15B to run a 51% attack for an hour. Obviously the price per PH would go up as you buy up that much hashpower (which wouldn't even be for sale), so this is a low end estimate, but your $300bn number is completely out of the park.