Canada’s Acuitas Therapeutics has filed a lawsuit against Arbutus Biopharma, challenging nine patents related to messenger RNA-delivery technology that Arbutus claims were used to help produce Pfizer/BioNTech’s COVID-19 vaccine.

Acuitas said it preemptively levied the complaint, filed in the U.S. District Court for the Southern District of New York, against Arbutus and its partner Genevant Sciences because it believes the two companies have erroneously alleged that Acuitas’ lipid nanoparticle delivery technology infringes on their intellectual property.

In its complaint, Acuitas argues that Arbutus and Genevant had nothing to do with the vaccine’s success and only sued after the Pfizer/BioNTech COVID-19 vaccine achieved “worldwide commercial success,” adding that the drugmakers are seeking “millions, if not billions, of dollars in wholly unjustified payments.”

The matter has significant financial implications for all parties. Pfizer reported that its COVID-19 vaccine earned the company over $36.7 billion in 2021 globally, while BioNTech will publish its full year revenue figures later this month. BioNTech previously estimated that it would earn COVID-19 vaccine revenues of up to $18.7 billion for the year.