Any process that stops, prevents, or reduces the frequency, rate or extent of the chemical reactions and pathways resulting in the formation of FasL.
Synonyms:
exact_synonym:
down regulation of FasL biosynthetic process; downregulation of FasL biosynthetic process; negative regulation of FasL anabolism; negative regulation of FasL biosynthesis; negative regulation of FasL biosynthetic process; negative regulation of FasL formation; negative regulation of FasL synthesis