South Africa's National Treasury on Thursday said it noted the "reckless manner" in which US-based trader Viceroy reported on Capitec bank and traded shares ahead of the release.
It said Viceroy stood to gain substantially from forcing the Capitec share price to fall by publishing its speculative report about the bank.
"Until two weeks ago, Viceroy operated anonymously and opaquely, and the reckless way in which it has released its report is clear proof that it is not acting in the public interest nor in the interest of financial stability in South Africa," the treasury warned.
It said Viceroy's report was not cause to place the bank under curatorship.
"Whilst the Treasury expects prudential and market conduct regulators in SA to consider all relevant reports in the public domain, and to act where any risks or transgressions in the law are identified, Treasury is of the view that the Viceroy report provides no basis to put any bank under curatorship."
National Treasury reiterated that it was satisfied with the assurance from the South African Reserve Bank that Capitec is well capitalised, liquid and solvent, and meets all prudential requirements.