Prototype install errors, solution inside
For anyone getting error messages when trying to install their new copy of Prototype for their PlayStation 3, Activision support has provided a temporary workaround while we wait for a patch via the PlayStation Network to fix the problem once and for all.
The issue occurs when your PS3 indicates you have insufficient hard drive space, even if you know you have more than enough room. You’ll have to change the amount of space on your hard drive by 700MB. You can do this by installing another PS3 game, downloading a game demo, removing downloadable content, or adding/removing music or movies from your hard drive.
The goal is to change the available hard drive space - try different variations. Once you’ve made the changes, try installing Prototype again. If you still cannot install the game, we recommend you contact Activision support.