Security on Superyachts

Is there anything known about the security on superyachts?
If you look at the amount of very violent kidnaps in Russia, a huge amount of ex military from all over the ex-eastblock travel free throughout the world etc, etc. the yachts also go to areas where you'll still find a good number of piracy, so am i very silly to think that for example an abromovich must have a half army aboard his ship (42 personnal and 8 staff on pelorus might be an indication).
This army might not be enough though since you need to detect anyone coming aboard, they might have to be ready for bigger weapons as well since "the trade" at this moment wont think twice to use anti tank weapons.

any knowledge on this tricky theme?