The rule for the fee, for Unity Pro is: "Those that have made $1,000,000 USD or more in the last 12 months AND have at least 1,000,000 lifetime game installs."

The rule for the fee, for Unity Pro is: "Those that have made $1,000,000 USD or more in the last 12 months AND have at least 1,000,000 lifetime game installs." Just the number of install plays 0 role, if the game didnt generate more than 1 million year, last year.