Sergii Grybniak
Founder of Opporty, whose OPP-token ICO the SEC charged as fraudulent — falsely claiming it was 'SEC compliant/registered' and exaggerating the platform's users. A 2025 final judgment ordered a $100K penalty and barred him from securities offerings.
Also known as: Sergey Grybniak
Bio
Sergii "Sergey" Grybniak founded Opporty International and led its OPP-token ICO. The SEC said he falsely claimed the ICO was "SEC registered" and "100% SEC compliant," exaggerated user numbers, misrepresented a partnership with a major software company, and used misappropriated third-party content to fake activity. [1][2]
Outcome
Charged in January 2020, Grybniak consented (without admitting/denying) to a February 2025 final judgment: permanent injunctions, a $100,000 civil penalty, a conduct-based injunction barring securities offerings, and undertakings to disable OPP tokens. [1][2]
Bracketed numbers refer to the numbered sources listed below.
Linked scams & cases
Sources (2)
See also
Luke BelmarIndividualsCryptocurrency influencer Luke Belmar (@lukebelmar on X) became the subject of controversy following allegations related to the promotion of a memecoin. Critics on social media alleged that Belmar used a series of posts referencing a forthcoming cryptocurrency project and a large-scale airdrop to generate interest in a token without explicitly identifying a specific contract address. Belmar published multiple posts discussing an upcoming memecoin, describing plans for what he characterized as a major airdrop and making comparisons to other cryptocurrency projects. Because no contract address was publicly provided, several tokens emerged claiming association with his statements. Critics alleged that this ambiguity enabled speculation around multiple tokens while avoiding a direct endorsement of any particular asset.
HEX / PulseChain (Richard Heart)ProjectsCrypto projects (HEX, PulseChain, PulseX) created by Richard Heart (Richard Schueler). In July 2023 the U.S. SEC sued him for offering unregistered securities that raised $1B+ and for allegedly misappropriating ~$12M for luxury goods (including a 555-carat diamond). A court dismissed the case in 2024 for lack of U.S. jurisdiction; there was no finding of wrongdoing and Heart denies the allegations.
This page was last updated on Jun 15, 2026. View revision history.
