It's been proven that companies do that.

现在已经证明了有公司就是这么做的

耶鲁公开课 - 金融市场课程节选

It's experience, it's proven track record, overall ability, overall intelligence.

CNN: Republican philanthropist pays pro-Gore legal bills

It's the disturbing truth that anyone can turn violent or deadly, and it's proven very difficult to identify who's vulnerable and what the trigger might be.

CNN: Autism link to violence is a myth

If it's proven that they have in fact conducted a nuclear test, does that really change the situation?

NPR: Diplomat Offers Analysis of North Korea Test