Pharmaceutical company Bayer. Sold HIV infected blood to poorer countries because they didn’t want to lose the investment they had in the blood.

Basically the blood was tested, found out it was HIV contaminated, went to a part of the world where they didn’t test as well. Messed with the results of the tests, and infected thousands of people with it, and eventually AIDS. All because the financial loss they would have taken from destroying the blood was considered too much.