[vel0city]

> Or just "rent" because that seems pretty close to the reality of the situation.

Rent has a defined time period. Buying a license in this case has an indeterminate time period. Buying a license is still very different from renting or leasing it.

[quesera]

Some rental agreements include automatic renewal unless cancelled by either party.

So, a rental agreement for a defined period (very short, instantaneous even), with automatic renewal.