Block.One, which conducted the world’s biggest initial coin offering (ICO) last year, has agreed to settle with the Securities Exchange Commission (SEC) for an unregistered sale of securities.

As part of the settlement, Block.One will pay a one-time penalty of $24 million. The federal agency noted that Block.One conducted its offering after publication of the DAO Report of Investigation, a 2017 report that examined the status and provided guidance for evaluation of digital token offerings.

“Block.one did not register its ICO as a securities offering pursuant to the federal securities laws, nor did it qualify for or seek an exemption from the registration requirements,” the SEC stated in its press release.

On its own website, Block.one clarified that the penalty was for an ERC-20 token, the most popular token framework used for offerings, that is no longer being used. The startup stated that the SEC has also granted it with a waiver for restrictions that apply to such settlements.

In past settlements, the agency has ordered issuers to return tokens to “harmed” investors, register tokens as a securities offerings, and file periodic reports about their status with it.

Block.one was the main backer in an offering that raised slightly more than $4 billion from the sale of 900 million EOS tokens between June 2017 and June 2018. EOS has positioned itself as a competitor to Ethereum, the world’s second-most valuable blockchain. The offering, which was conducted at the height of a mania over cryptocurrencies and blockchain technology, was accomplished without a live product.

Since the offering, Block.one has run into problems of its own. Online publication Coindesk recently reported of problems with governance of its blockchain. The startup also has not provided full accounting for its use of cash raised from the offering.