I am starting this thread along the lines of the "Earning EQM on Turkish G class" one.

It appears that brussels airlines (SN) is no longer awarding MileagePlus members miles for flights in K class. This is not all that surprising. brussels airlines is a member of the Miles&More gang, and the major airlines in that gang stopped giving out miles for K class.. so why shouldn't SN too?

However, UA's page for SN earnings shows 100% RDM and PQM earning for K class. For now.

In January I flew SN K class (SN coded, SN operated), the miles did not post, I filed a missing miles claim, that claim was rejected by SN due to "class of service not eligible", UA put it through again as M class and then it worked. Miles appear in my MP statement as SN M class.

This was the same solution that UA was doing earlier with missing G miles on TK. So if TK G is any precedent, be prepared to have to fight for your SN K miles, and be prepared for a charge in earning rules for SN K class.