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If you are creating a game or commercial application using UDK for sale or distribution to an end-user or client, or if you are providing services in connection with a game or application, the per-seat option does not apply. Instead the license terms for this arrangement are $0 (zero) up-front, and a 0% royalty on you or your company's first $5,000 (US) in UDK related revenue, and a 25% royalty on UDK related revenue above $5,000 (US). UDK related revenue includes, but is not limited to, monies earned from: sales, services, training, advertisements, sponsorships, endorsements, memberships, subscription fees, rentals and pay-to-play.