It's not a tax credit per se. It's just that right now, if they're operating a business, they would be entitled to just the regular deductions that anyone who's operating a business or earning income from property is entitled to—
Evidence of meeting #142 for Finance in the 44th Parliament, 1st Session. (The original version is on Parliament’s site, as are the minutes.) The winning word was budget.
A video is available from Parliament.