Greece is leading the controversy over the infamous warrants tied to AEP, it’s in the courtrooms of the United Kingdom, bringing an action, according to Bloomberg, against Wilmington Trust, the trustee of the securities in question, according to court documents filed last week.

The Greek government’s goal is to establish the legality of the early repurchase decision for all outstanding securities maturing in 2042 and to confirm that the calculation of the repurchase price was correct.

The appeal comes as some holders of the securities challenged the legality of the notice issued by Greece in April, triggering a related buyback clause (call option) with a settlement date of May 14. At the same time, investors are also questioning the method of determining the buyback price, according to an official statement from the Greek side.

The identity of the warrant holders opposing the exercise of the buyback clause has not been disclosed. Greece is represented by law firm Cleary Gottlieb Steen & Hamilton, which did not respond to a request for comment, and a spokesman for Wilmington Trust declined to comment.

The warrants in question are financial instruments that yield returns only when a country’s economic growth exceeds predetermined thresholds.