I believe we were able to upgrade from 7.5 to 9.1 without getting new license files but that was a couple of years ago.
Keep in mind that you will need different versions of Java and Oracle to support these two versions. That is a bit tricky to do concurrently on a single server and licenses are tied to a specific IP address. You could try to run 7.5 with current versions of these products but that was never tested. We had issues with Java and Oracle compatibility when doing our upgrade.
At the moment We use HP PPM 8.04 and the project is thinking the possibility to install a new version of HP PPM (9.22) but They don't want use the upgrade option ... They want a clear installation ... so my question is .... they need buy licenses to install the new version or they can use the licences of HP PPM 8.04.
I believe they would need specific licenses to do this. I can get you connected with the appropriate sales/licensing team to discuss this option if you would like. Let me know if you would like to talk offline.
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