Pavel and Nikolai Durov reported that they raised $850 mln in the second round of their initial coin offering (ICO) in a notice signed today with the US Securities and Exchange Commission.

The ICO sought investment to support the development of the Telegram messenger app and its own Blockchain platform Telegraph Open Network. While the document does not disclose the identity of investors, 94 different entities took part in the ICO, which started on March 14. In the column wherein the applicant specifies which type of securities are on offer, the document states “Purchase Agreements for Cryptocurrency.”

The offering was given under Federal Exemption 506(c), which states that, “a company can broadly solicit and generally advertise the offering and still be deemed to be in compliance with the exemption’s requirements” so long as certain conditions are met. First, all investors in the offering must be accredited, and second, the issuer must take reasonable steps to verify said accreditation.

The first round of the ICO took place from Jan. 29 to Feb. 13, and managed to attract $850 mln from 81 investors.

According to news agency Vedomosti, one of the investors in the first round of the ICO was Russian billionaire Roman Abramovich. Persons familiar with the matter told Vedomosti that Abramovich invested $300 mln. Jon Mann, Abramovich’s spokesperson, made no comment as to whether Abramovich took part, but denied the $300 mln claim. Two investors have come forward publicly with their support and investment in the ICO; founder of payment service provider Qiwi, Sergei Solonin, and founder of Wimm-Bill-Dann foods, David Yakobashvili.

Current regulation of ICOs by the SEC is based on legislation from the 1930s. One expert told Cointelegraph that in order for ICOs to operate efficiently, authorities need to amend the 80-year-old regulation.