The IYT "Master of Yachts" and the IYT "Small Powerboat & RIB Master" certificates do not require a "commercial endorsement" because they are commercial certificates.
The MCA has recognised 3 levels of IYT Master of Yachts Certificates and the Small Powerboat and RIB Master Certificate as being "Commercial" in their own right. They are:

  • Master of Yachts Coastal/Mate 200 gross tons and Master for vessels <24 m
  • Master of Yachts Limited <200 gross tons
  • Master of Yachts Unlimited <200 gross tons
  • Small Powerboat and RIB Master

The "Yachtmaster" certificates issued by the Royal Yachting Association (RYA) are recreational certificates and these certificates do require a "commercial endorsement" if one wishes to work commercially.