Here is the document granting the vaccine manufacturers immunity:

Department of Health and Human Services Issues Declaration Under the PREP Act to Provide Immunity for Activities Related to Medical Countermeasures against COVID-19
Posted on Mar 26, 2020

By: Stacy L. Hanefeld

The Department of Health and Human Services (“HHS”) recently issued a declaration under the Public Readiness and Emergency Preparedness (“PREP Act”) to provide immunity to liability for activities related to medical countermeasures against COVID-19 (“the Declaration”). The Declaration is published in the Federal Register. It is effective retroactively to February 4, 2020 and remains in effect through October 1, 2024.

What is the PREP Act? The PREP Act authorizes the Secretary of HHS to issue a PREP Act declaration that provides immunity from liability for any loss caused, arising out of, relating to, or resulting from administration or use of countermeasures to diseases, threats, and conditions determined in the declaration to constitute a present or credible risk of a future public health emergency. In general, the liability immunity applies to entities and individuals involved in the development, manufacture, testing, distribution, administration, and use of medical countermeasures described in the declaration. A PREP Act declaration is specifically for the purpose of providing immunity from liability and is different from, and not dependent upon, other emergency declarations issued by HHS or other governmental agencies.
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