RAPAPORT... A five-year dispute between diamond manufacturer Pluczenik and broker W. Nagel is set to continue, despite a recent court ruling. Pluczenik has submitted an appeal to the UK Supreme Court, seeking to overturn a directive for its Belgium-based business to pay Nagel $3.3 million over a breached pact made nearly 25 years ago. The sides had different interpretations of the nature of a 1994 verbal agreement between the late Isaac Pluzcenik and Willie Nagel, explained Pluczenik's lawyer, Francine Wachsstock of WS Law. This is an old commercial dispute that is based on an oral contract, which is difficult to prove and is recognized in some jurisdictions but not in others, she added. Under the pact, Nagel said he agreed to reduce his commission for services at De Beers sights on condition Pluczenik would retain Nagel as its broker for as long as it was a De Beers client. Chaim Pluczenik, who took over as CEO after his father Isaac's death in 1997, claimed the company had promised not to hire a different broker, but had the right to go broker-free when De Beers allowed such a move in 2013. Pluczenik ended the relationship in July of that year, leading to the dispute over the nature of the agreement. In its November 28 ruling, the Court of Appeal of England and Wales sided with Nagel, upholding an earlier decision by the London Mercantile Court. Pluczenik, who is now taking the case to the UK Supreme Court, has also initiated litigation in Belgium, claiming a foreign judgment should not apply to a Belgian entity. Meanwhile, Pluczenik has another ongoing lawsuit against Nagel, filed in 2014 in a Belgian court, in which it is claiming damages of EUR 20 million ($22.8 million) that resulted from "professional mistakes" made by Nagel during their work together, Wachsstock said.Image: A Pluczenik marketing event (Pluczenik).