Even with the price back above $8,000, many of the so-called miners that perform the complex calculations to generate the digital currency are at risk of turning unprofitable. If prices drop below that threshold again for an extended period, there will likely be a swifter consolidation to industrial-scale mining. That could knock out the last guy-in-a-dorm-room operations and leave holders of the currency vulnerable to the dictates of the big miners.
“It’s totally different this year than last year,” Silicon Valley venture capitalist Bill Tai said in an interview. “The bitcoin mining industry was this mysterious dark cottage industry, and it’s about to grow up and about to have elements of institutional scalability at all levels."
Smaller miners will drop out, and only five to 10 of the largest will survive and be profitable, said Tai, who serves as chairman of Hut 8 Mining Corp., the capital financing arm in North America for Amsterdam-based Bitfury Group Ltd., one of the biggest makers of crypto-mining equipment. When the price of Bitcoin approached $19,000 last year, Bitfury had to turn some customers away as $1.9 billion of orders streamed in, he said.
More concentration could also hold a lot of sway over Bitcoin’s price. Miners hold between 20 percent and 30 percent of all Bitcoins, according to Lucas Nuzzi, a senior analyst at Digital Asset Research. Bitfury alone has mined more than 1 million Bitcoins, Tai said. The company has already sold coins to defray operating expenses. If miners are forced to sell more, that could depress Bitcoin’s price.
With mining power -- so-called hashrate -- aggregated in fewer hands, that also increases the risk that a few miners could band together to execute a so-called 51-percent attack -- where they would control enough of the transactions to dictate changes in the development of the blockchain to suit their preferences.