Coinbase Inc. A research firm hired by the Federal Deposit Insurance Corp. in 2022. It was revealed that crypto banking activities were stopped or blocked in many US banks by the (FDIC).

Coinbase appointee History Associates Inc. sued the FDIC and the Securities and Exchange Commission in June and ultimately gained access to some of the FDIC’s internal communications.

Heavily blacked-out documents released on Friday show that the banking regulator has halted the operations of banks that offer or plan to offer products and services related to the digital assets sector.

“We respectfully request that you cease all crypto-asset-related activities,” the regulator said in one of 23 letters shared by the crypto exchange. “The FDIC will notify all FDIC-supervised banks once their supervisory expectations for participating in crypto-asset-related activities are determined.”

The industry has long complained that companies and prominent crypto figures excluded from U.S. banking are being denied access to banking services.

Paul Grewal, Coinbase’s chief legal officer, argued that these letters are concrete evidence that crypto businesses are being systematically blocked from banking by the regulator.

“The letters show that this is not a conspiracy theory and not just paranoid speculation by the industry,” Grewal said in an interview with CoinDesk.

“The FDIC had a determined plan to deny banking services to a legitimate American industry. This is a matter for everyone to seriously consider.”

While the text of most FDIC letters is blacked out, the documents are dated through 2022 and make clear that crypto activities that banks submit for FDIC approval will not move forward until questions are answered about how banks will meet compliance requirements.

In some cases, activity was halted before it began, in others the agency recommended that they halt further expansion or shut down a line of business before banks had completed reviewing the firm’s request.

“We expect you to satisfactorily resolve these and any subsequent questions before proceeding with action,” one typical example read.

Some confidential letters contained very complex and demanding questions addressed to banks. But several documents also showed that the agency is still unsure of what regulatory documents are required before approving a crypto business.

While the three main U.S. banking regulators — including the Federal Reserve and the Comptroller of the Currency Office — have issued some broad warnings regarding crypto, the agencies have not introduced a formal set of rules governing the industry.

Grewal said the next step in the federal courts is to request that the letters be unblocked and clarify which agencies are subject to what questions, what services they want to provide. This step will reveal the “why” of the FDIC’s stance.

“Even though the federal courts have repeatedly ordered the FDIC to produce this information, they are still moving slowly, and we think that needs to stop,” Grewal said.

The banking exclusion campaign is known in the industry as “Operation Chokepoint 2.0”, an effort by a previous government initiative to cut off non-illegal but controversial businesses from banking.

The issue came up again this week at a hearing held by the House Financial Services Committee. Crypto business leaders expressed how their companies were excluded from financial services.

“We, too, have been excluded from banking,” said Nathan McCauley, CEO of Anchorage Digital. “This is especially surprising because we are a national bank ourselves.”