Swiss drugmaker Roche is petitioning the U.S. government in direct talks for import tariff exemptions, arguing the products it ships into the United States are offset by its exports of U.S.-made drugs and diagnostics.

Roche’s exposure to the tariffs is mostly limited to four medicines, three of which it already produces in the U.S., according to CEO Thomas Schinecker, who declined to reveal what these assets are.

Roche has said it is petitioning the Trump administration for an exemption from threatened tariffs for pharmaceuticals, arguing there is no trade imbalance in its US business.