Ability to prohibit merging of tickets across organizations

Hi, we think it a good idea to restrict merging of tickets from different organizations. Mostly to prevent human error, as one of our agents accidentally merged two tickets from different companies.  An easy mistake when ticket numbers are similar, but sadly for us it meant that details for company A were passed to company B.  We can't see a reason in our business where we would need to merge tickets from different organizations so would like to have a setting that allows us to prevent this - could even be a permissions thing that is blocked at agent level, but allowed by admins?

Thanks