Fidelity Digital Assets Says Bitcoin Security Can Hold as Mining Rewards Decline

Fidelity Digital Assets has rejected concerns that Bitcoin’s long-term security will weaken as mining rewards shrink, saying the network’s incentive structure can remain strong even as block subsidies decline. According to Cointelegraph, a new research report authored by Fidelity research analyst Daniel Gray argues that Bitcoin’s security is supported by more than block rewards, pointing to transaction fees, market incentives, and other economic forces that encourage miners to keep securing the blockchain and make sustained attacks prohibitively expensive.

The report challenges a longstanding criticism that each quadrennial halving undermines Bitcoin’s security by reducing new coin issuance, potentially eroding miners’ incentives unless transaction fees rise enough to compensate. The debate remains a central long-term question for Bitcoin (BTC), which follows a fixed supply schedule that gradually reduces issuance until block subsidies eventually disappear. Since April 20, 2024, miners have received a subsidy of 3.125 BTC per block, down from 6.25 BTC in the prior halving cycle. Gray said lower issuance has not translated into weaker incentives because Bitcoin’s rising price has more than offset the decline in block rewards. He cited average daily miner revenue growth from roughly $26,300 during Bitcoin’s first halving cycle to more than $40.2 million today, writing that miner incentives—and by extension network security—have historically strengthened alongside Bitcoin’s price.

While Fidelity’s report maintains that Bitcoin’s long-term incentive structure remains intact, publicly traded mining companies are facing near-term financial pressure. Some industry analysts have described the current environment as among the most challenging on record, citing lower mining rewards, rising costs, and intensifying competition. In response, several miners have diversified into artificial intelligence and high-performance computing, using existing power infrastructure and data center assets to serve demand for AI workloads rather than relying solely on Bitcoin mining.

A recent VanEck report estimated that publicly traded miners could require up to $50 billion in additional capital to fully transition to AI infrastructure, highlighting the scale of the shift. Blocksbridge Consulting, writing in a Miner Weekly publication, said Bitcoin mines can operate with relatively simple buildings, modular infrastructure, and ASIC fleets that tolerate fast curtailment, while AI and HPC facilities require higher standards for uptime, cooling, electrical redundancy, networking, and customer support.