It simply was not worth taking a chance, the companies reasoned. No matter if they warned of any and all known dangers of the vaccine. No matter if they could easily explain to the scientific community the illnesses and deaths that were bound to occur by coincidence when more than 100 million people were vaccinated. The fact remained that the companies could be sued, and they could lose big. Even if they won, they could be saddled with immense costs of defending themselves against a barrage of lawsuits.