When we sell flights on SQ, a prompt comes up telling us if the booking code does not earn miles. For example, if I sell Q class the warning flag comes up:

1 SQ 11Q 01SEP Q LAXSIN SS1 235P 110A 03SEP J /DCSQ /E
ALL SECTORS IN ITINERARY NOT ELIGIBLE FOR FFP MILES
- MAX BAG WEIGHT OF 32KG/PIECE DUE OCCUPATIONAL HAZARD -
ADV PAX THAT CARRYING OF LIGHTERS ON THEIR PERSON HAND-
CARRY OR CHECK-IN LUGGAGE IN THE STERILE AREAS OF
AIRPORTS OR ONBOARD AN AIRPLANE IN USA IS PROHIBITED

But if I sell W class it doesn't:

1 SQ 11W 01SEP Q LAXSIN SS1 235P 110A 03SEP J /DCSQ /E
- MAX BAG WEIGHT OF 32KG/PIECE DUE OCCUPATIONAL HAZARD -
ADV PAX THAT CARRYING OF LIGHTERS ON THEIR PERSON HAND-
CARRY OR CHECK-IN LUGGAGE IN THE STERILE AREAS OF
AIRPORTS OR ONBOARD AN AIRPLANE IN USA IS PROHIBITED
ADV PAX LOCAL CHECK-IN COUNTER CLOSURE TIMING

You will get mileage credit on W class.