The short answer: If you are in Europe, LINKSPREED UG, based in Germany. Everywhere else, LINKSPREED LLC, based in the United States.
Why it is split this way: Serving European users through a German entity keeps the European business inside the EU legal and regulatory framework. The US entity covers the rest of the world.
What it means for your data: For European users, data is stored in Germany or elsewhere within the EU. Your UIID credentials themselves are device-based and biometric-secured, so there is no central credential store in the first place — the exception being the encrypted UIID Cloud backup, if you leave it enabled.
What it means for your contract: The applicable terms follow the entity that serves your region. Both entities' registered locations, the Terms of Service and the Privacy Policy are published at legal.linkspreed.com.
Where the team sits: The registered headquarters is in Albuquerque, New Mexico, but the team works fully remotely and internationally.