Moderna is suing Pfizer and its German partner BioNTech for patent infringement in developing the first US-approved COVID-19 vaccine, alleging they copied technology developed by Moderna years before the pandemic. It is reported by Reuters with reference to a press release from the company.

Shares of Pfizer fell 1.4% on the news, while shares of BioNTech fell about 2%.

The lawsuit, seeking unspecified monetary damages, was filed in the US District Court in Massachusetts and the District Court of Dusseldorf in Germany, Moderna said in a statement.

“We are filing these lawsuits to protect the innovative mRNA technology platform that we have developed, invested billions of dollars in creation and patented in the decade leading up to the COVID-19 pandemic,” Moderna CEO Stephane Bancel said in a statement.

Moderna Inc on its own and Pfizer Inc in partnership with BioNTech SE were the first two groups to develop a coronavirus vaccine.