The Service Contract will start at the end date of the previous Service Contract, or at the order date of the license if it did not yet have a Service Contract. The service contract can be renewed when it expires after 1 year. You can order the service contract directly with PL/SQL Developer or at a later time. Without this contract, you will receive only patch releases of the PL/SQL Developer version you purchased. If you order an Annual Service Contract with your PL/SQL Developer licenses, you are entitled to receive technical support by e-mail and free product upgrades for the period of 1 year. If you have a worldwide license for the software product, you are entitled to use the software product with an unlimited number of developers within the legal entity of the license holder in any country. If you have an unlimited user license for the software product, you are entitled to use the software product with an unlimited number of developers within the legal entity of the license holder and within the country of the license holder. You may use the software product for the number of named licensed developers within the legal entity of the license holder and within the country of the license holder. Therefore you need just one license for one named user, even if you are running multiple instances on multiple machines. PL/SQL licenses are per named user, and not per PC, Server, Database or Location.
One software license is required per user.