That&#x27;s what the FDA does now, yes. However, the polio vaccine was introduced when the FDA had weaker powers. It wasn&#x27;t until after the Thalidomide tragedy and the 1962 Kefauver-Harris Amendment where pharmaceutical companies also needed to demonstrate effectiveness. Before then, companies only needed to demonstrate safety.<p>As it was, the Cutter polio vaccine incident shows that making the vaccine was not easy.<p>&gt; I&#x27;m sure that Salk knew ...<p>How are you sure? Is this discussed in his biography or autobiography? I see the topic is covered in Jane S. Smith&#x27;s &quot;Patent the Sun&quot;, but I haven&#x27;t read it.<p>Other vaccines (or vaccine preparations) at the time were patented. Was your described behavior typical for them?