Canada’s tech industry is warning that the country continues to lose its best and brightest entrepreneurs to the U.S., an issue that has taken on new urgency as tariff threats have prompted Ottawa to try to diversify away from the U.S. economy.

This week, various tech entrepreneurs, politicians and economists began to weigh in on data that show just how big the problem has become. According to recent figures, there are at least 517 U.S.-based tech firms with Canadian founders — or, entrepreneurs who were educated in Canada but later left for the U.S. — that have together raised more than US$400 billion.

“The numbers make it clear that Canada’s founders and entrepreneurs are leaving in droves — and they are taking the future value they will generate with them,” said Lucy Hargreaves, co-founder of the business advocacy group Build Canada, who issued a call to action in the form of a LinkedIn essay that triggered an online conversation about the trend.