A more recent strand of research into this topic claims that intervention operations can be effective when they signal future monetary policy operations, which are perceived to be more effective in altering asset prices, including exchange rates. The problem with this view is that it means that sterilised intervention is not an independent tool that can be used to influence exchange rates.
It needs a supporting monetary policy stance to be effective. We are left with the conclusion that foreign exchange market-sterilised intervention by itself has only a limited impact on exchange rates. This is underscored by the reported purchase by Japanese authorities of roughly $ billion against yen in April of last year that barely budged the dollar/yen exchange rate.