“I guess that depends on how you define “concede”. “
Gore on 12/13/00:
“Now the U.S. Supreme Court has spoken. Let there be no doubt, while I strongly disagree with the court’s decision, I accept it. I accept the finality of this outcome which will be ratified next Monday in the Electoral College. And tonight, for the sake of our unity as a people and the strength of our democracy, I offer my concession. I also accept my responsibility, which I will discharge unconditionally, to honor the new President-elect and do everything possible to help him bring Americans together”
That is pretty much how I define concede. If Trump makes a similar speech that would be fine.