Any process that activates or increases the frequency, rate or extent of intralumenal vesicle formation.
Synonyms:
exact_synonym:
positive regulation of endosome membrane budding; up regulation of endosome membrane budding; up regulation of intralumenal vesicle formation; upregulation of endosome membrane budding; upregulation of intralumenal vesicle formation
narrow_synonym:
activation of endosome membrane budding; activation of intralumenal vesicle formation