Ireland's John Lacey will referee Scotland v England at BT Murrayfield on Saturday, February 6, and a week later his compatriot, George Clancy, will preside over proceedings at Principality Stadium, Cardiff, for the Wales v Scotland game (February 13).
They are joined by 2015 Rugby World Cup Final referee, Nigel Owens (Wales), who will be in control of France v England (March 19), the final match of this year's tournament.
Commenting on the appointments Ed Morrison, Appointments Administrator, PRO12 Rugby said:
"It's great to see three of our referees participating in the 2016 RBS 6 Nations and behind the scenes we are working very hard to invest in the development of GUINNESS PRO12 officials across all four unions involved in our championship.
"Testament to our revised training and workshop programmes, the next generation of referees are progressing through the ranks and this is exemplified by Andrew Brace (Ireland) and Lloyd Linton (Scotland), who will be in charge of the Under 20's Six Nations Scotland v England and Under 20's Six Nations Italy v England respectively.”
GUINNESS PRO12 referees involved in the 2016 RBS 6 Nations:
John Lacey (Ireland): Scotland v England;
George Clancy (Ireland): Wales v Scotland.
Nigel Owens (Wales): France v England;
Assistant Referees in RBS 6 Nations above three plus
Marius Mitrea (Italy): Scotland v France;
Leighton Hodges (Wales): France v England
Under 20's Six Nations (only first two rounds selected to date)
Andrew Brace (Ireland): Scotland v England;
Lloyd Linton (Scotland): Italy v England.