Investing.com -- The Bank of Lithuania has launched a probe into Robinhood’s (NASDAQ: HOOD ) new blockchain-based “Stock Tokens,” following concerns raised by OpenAI over their association with the tokens. The central bank confirmed to CNBC on Monday that it had reached out to Robinhood for further details on the structure and marketing of tokens linked to private companies like OpenAI and SpaceX.

“We have contacted Robinhood and are awaiting clarifications regarding the structure of OpenAI and SpaceX stock tokens as well as the related consumer communication,” Bank of Lithuania spokesman Giedrius Šniukas told CNBC via email. “Only after receiving and evaluating this information will we be able to assess the legality and compliance of these specific instruments.”

The scrutiny comes just a week after Robinhood launched its Stock Tokens product across the European Union, promising tokenized access to shares, including those of privately held firms, through blockchain technology. Lithuania is Robinhood’s lead regulator in the EU following its receipt of a brokerage and crypto asset license from the country’s central bank.

The product has raised immediate questions from OpenAI, which publicly distanced itself from Robinhood’s offering. “We did not partner with Robinhood, were not involved in this, and do not endorse it,” OpenAI said in a post on X, also stating, “These ‘OpenAI tokens’ are not OpenAI equity.”

Robinhood, in turn, defended the tokens by highlighting their basis in ownership stakes meant to give investors indirect exposure to private markets. CEO Vlad Tenev said on X, "While it is true that they aren’t technically ’equity,’ the tokens effectively give retail investors exposure to these private assets."

Still, regulators remain cautious, especially around the clarity and legality of how these digital instruments are presented to retail investors. Šniukas told CNBC that information to buyers “must be provided in clear, fair, and non-misleading language.”

For now, Robinhood’s EU expansion in tokenized equities faces a potentially turbulent compliance review, with Lithuania’s findings likely to influence broader regulatory scrutiny across the bloc.