Caterpillar, the world’s largest construction equipment manufacturer, has asked a federal judge in Delaware to dismiss an antitrust lawsuit accusing the company of conspiring to block a competitor from entering the market for heavy construction equipment, saying there was no direct evidence to support the claims.

In a brief filed Tuesday in Delaware federal court, lawyers for Caterpillar Inc. said the four-year-old suit from International Construction Products had failed to make any specific allegations linking the Illinois-based manufacturer of construction and mining machinery to an alleged plot to suppress competition and fix prices.