Any process that stops, prevents, or reduces the frequency, rate or extent of a process in which oskar mRNA is transported to, or maintained in, the oocyte pole plasm.
synonyms:
inhibition of pole plasm oskar mRNA localization,
down regulation of pole plasm oskar mRNA localization,
negative regulation of oocyte pole plasm oskar mRNA localization,
negative regulation of pole plasm oskar mRNA localisation,
down-regulation of pole plasm oskar mRNA localization,
downregulation of pole plasm oskar mRNA localization