Hi Kumar,
If you need o upgrade from 7.6.1 to 7.6.1.3 version is possible directly without having to upgrade to 7.6.1.2 previosusly, it's not a requirement.
This fix pack updates IBM® Maximo® Asset Management version 7.6.1, 7.6.1.1, and 7.6.1.2.
In this url detail step by step for how do a migration to 7.6.1.3:
https://www.ibm.com/support/pages/node/6609332
Regards
Flores
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Flores Gallegos Romero
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