Patch deployment responsibilities

[vman]

Patch deployment checks

while change management will own the patch deployment validation
that the patch will not have an adverse effect on the environment

but are who is responsible for actually implementing the patch
and who will be responsible for checking that the patch is implemented in the correct manner into production environment

[Diarmid]

You may be confusing doing with managing.

The patch is implemented by an appropriately (technically) qualified individual and that person is answerable to whoever is managing the implementation (which might be an implementation manager, but in a small organization that will be a role rather than a job)

Same answer for your second question. (Yes, it's a sad fact: you can have all these ITIL roles in place, but sometimes you still need to use real people with technical know-how to do real things)

In both cases change management will be informed of the completion (and, of course of any issues!) as part of the change review and sign off requirements.
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