In order of size of company, i suspect a more realistic list would be:   BitFury is 1st, KnCMiner 2nd, Bitmain 3rd, Cointerra 4th, etc..    this size rating probably works regardless of whether you measure by petahash or revenue.  I doubt asicminer is even relevant at this time.  They're no longer Huge.  They were HUGE when the network was less than 1 Petahash - now they're a minnow - and got left behind when the others designed better chips.