瑜伽師地論略纂 4.19

4.19

增長、不增長業中，「八、自性無記業」者，謂善不善非業道攝中下品性，非三性中無記性也，自體不增名無記故。或三性中無記之業。

Regarding accrued and unaccrued karma: 'Eighth, karma neutral by self-nature' refers to the middling and lower qualities of wholesome and unwholesome karma not subsumed under paths of action, not the neutral nature among the three natures, because its self-nature does not increase and is called neutral. Alternatively, it refers to neutral karma among the three natures.