The USA international arrived at the Britannia Stadium in January 2013 with a reputation as a tricky winger with a keen eye for goal.
He has, however, struggled to make an impact in England - making just three substitute appearances for the Potters in the Premier League.
A loan spell at Sky Bet Championship outfit Barnsley was intended to help get important minutes under his belt, but that agreement was cut short in March.
Shea has been able to remain part of his national team set-up despite his lack of competitive action and will be hoping to compete at the World Cup finals this summer.
Uncertainty shrouds his long-term future at club level, though, with the issue set to be addressed in the summer.
Were Stoke to make him available, Toronto general manager Tim Bezbatchenko has revealed that his club would be keen on acquiring the services of the 24-year-old former FC Dallas midfielder.
He told the Toronto Sun: "Yeah, 100 per cent.
"I mean, Brek Shea is a dynamic US international. I think you'd take any of these guys seriously."