In conclusion, the Board of Appeal did not err when it held, in essence, that the signs at issue were visually similar to a low degree and phonetically similar to a degree ranging from average to high, depending on the part of the relevant public in question. (curia.europa.eu)
he is not merely seeking a new assessment of the facts from the Court , but is alleging that the Court erred in law.
to err: errar, equivocarse
to err in law: cometer errores de Derecho (en contraposición a errores de hecho)