Elizabeth Warren presses Commerce over Bitmain security review

Senator Elizabeth Warren has asked the US Commerce Department to explain how it is handling reported security concerns tied to Bitmain, the Chinese company that makes much of the world’s Bitcoin mining equipment. 

Her request adds to growing attention on foreign-made mining hardware used across the US crypto sector.

Bloomberg reported that Warren sent a letter on Thursday to Commerce Secretary Howard Lutnick asking for documents and communications related to Bitmain and any steps the department has taken to address “potential national security concerns.” The report said the letter focused on how Commerce is handling the matter and whether political influence has affected those decisions.

The request follows months of reporting about federal scrutiny of the company. A national security inquiry into Bitmain remains unresolved, and the current status of that review is still unclear. The same report noted that cases of this type can continue for years without a public enforcement action.

The Department of Homeland Security opened a probe known as Operation Red Sunset to examine whether Bitmain’s mining machines could create espionage or sabotage risks. That review looked at whether the machines could be remotely accessed or used in ways that could threaten US systems.

Moreover, a May 2024 federal review raised “national security concerns” about Bitmain machines used near a US military base. 

Separately, Cambridge’s Digital Mining Industry Report said the ASIC mining hardware market is highly concentrated, with the top three manufacturers controlling more than 99% of market share and the largest vendor alone holding 82%.

Pressure on Bitmain has not been limited to the DHS review. In February 2025 US miners faced delivery delays after customs scrutiny affected Bitmain equipment shipments. TSMC halted shipments to Sophgo, a Bitmain-linked chip design firm, after a chip linked to Huawei was discovered. Later, the US added Sophgo to its trade blacklist.

These steps widened the focus from mining hardware alone to Bitmain’s broader business links. They also placed more attention on how Chinese crypto hardware suppliers interact with US trade and security policy.

Trump-linked mining ties add another layer

Bitmain also has business ties to American Bitcoin, a mining firm backed by Eric Trump and Donald Trump Jr. The company agreed last year to acquire 16,000 Bitmain rigs for $314 million, according to securities filings cited by Bloomberg. Warren’s request seeks information on any communications involving Bitmain, Commerce officials, and Trump family interests.

At the same time, Bitmain has been building a larger US presence. In July 2025 the company planned its first US-based manufacturing site, with initial output expected in early 2026 and a broader ramp later in the year. That plan now sits beside an unresolved federal review and renewed political scrutiny in Washington.