Amy Winehouse's U.S. record label is threatening to sue American record stores that are selling pirated copies of her as-yet-released in the States debut album. Universal planned for Frank to hit stores in November (06), off the back of the success of her sophomore release Back To Black - which has been a massive hit in America and sold nearly 1 million copies to date. But its success has prompted a huge demand for Frank, and a number of stores are reportedly selling illegally imported copies - with sales reaching 18,000.