Who has 300 Pentahash?
none because it mean that someone is holding more than 33% of the network, if we talk as a single farm, and pool at best have 20%
well if you want to go by country than chinese have double of that...
a single farm can't get never 51% of network ( I think after reading some points of protocols and mining farms)
that's not the point, because a pool can easily reach that number, and it was proven in the past with ghash
and anyway if all chinese farm work together and merge their huge farm in the future, for whatever reason they could easily surpass 51%...