Daniel Yu, the founder of Gotham City Research LLC, has appeared before Spain's Audiencia Nacional as part of an ongoing investigation into potential market manipulation following a report released by his firm in January 2024. The report allegedly contained misleading information about the pharmaceutical company Grifols, which has been accused of intentionally trying to lower the company's stock price by disseminating false information.

Yu has been under investigation for over a year, and the Spanish Anti-Corruption Prosecutor's Office is attributing a market fraud crime to him related to the publication of this report. The investigation has raised questions about the ethics of short-selling practices and how they can impact the market stability of publicly traded companies, particularly in the pharmaceutical sector that often relies on investor confidence.

During his court appearance, Yu's interrogation was conducted with specialized simultaneous translation due to the economic and financial complexities of the case. The unfolding situation continues to attract attention in Spain, as it highlights broader concerns about transparency and integrity in financial markets, especially against the backdrop of increasing scrutiny on hedge funds and their impact on vulnerable companies in the stock market.