Solaris patch access policy in Fujitsu systems

Hi,
I would need help to understand Solaris patching policy in Fujitsu systems.
PRIMEPOWER and SPARC Enterprise/Solaris Patches
Which is the difference between "Public patches and patch clusters" and "All Patches"?

Do I need a maitenance contract with Fujtisu to download "Public patches and patch clusters" or only having bought
a primepower system can I have access to these patches?
Regards,
Mario.