Large Scale Mining operations
We can look at block explorers to see which entities are finding the most blocks. Those entities are either big mining pools or industrial Bitcoin mines. We took a look at https://blockchain.info/pools to see the hashrate distribution, which is depicted in the following figures:

Fig. 7.2: Hashrate distribution (4-day average). Image courtesy of blockchain.info (you can take a look at https://blockchain.info/pools or https://www.smartbit.com.au/ to see the latest distribution)

Fig. 7.3: Hashrate distribution. Image courtesy of https://www.smartbit.com.au/ (you can take a look at https://blockchain.info/pools or https://www.smartbit.com.au/ to see the latest distribution)
We can see that the two biggest holders of hashrates are F2Pool and AntPool; those are the mining pools. So are BTCChina Pool, Slush, BW.COM, Eligius, BitMinter, and GHash.IO.
On the other hand, BitFury, KnC Miner, 21Inc., and Telco 214 are industrial miners ranging from very large to small. Let...