An equipment company is not liable for the actions of a thief who ripped off one of its customers in an online scam, a federal judge held Monday.In a written opinion, U.S. District Judge John Robert Blakey granted summary judgment in favor of Runnion Equipment Co. in a breach of contract lawsuit brought by Landale Signs and Leon Ltd.Blakey did not rule on the merits of the contention that Landale and Runnion formed an implied contract to keep certain information confidential while carrying out a deal for Landale to buy a …