Sporting are enduring one of the worst periods in their history, languishing 10th in the league, and the 24-year-old Dutchman is their top scorer with eight goals in the championship.
"Sporting are in talks with Norwich regarding the transfer of Ricky Wolfswinkel," said a statement from the Lisbon club published on stock market regulator CMVM's website. Sporting is a listed company.
With the club's presidential election looming this weekend, the possible sale of the versatile and agile Van Wolfswinkel has angered candidates.
"Sporting should not have to sell players to pay salaries. We cannot accept that," Bruno de Carvalho, the front-runner in the polls to be the next president, told o Jogo daily.