Spanish FA decides against matchfixing probe
Taped conversations, collected by a judge as part of an investigation in Hercules' hometown of Alicante, have been widely reported in local media, allegedly suggesting the club tried to influence the outcome of matches.
Hercules have denied any wrongdoing.
"(The court) has ended the possibility that the conversations, which are the basis for the accusations, can be used..." the federation said in a statement on their website.
The judge ruled that releasing the tapes would violate the privacy and individual rights of those involved. Without any further evidence with which to proceed the RFEF's competitions committee "decided unanimously not to open a disciplinary investigation."
Hercules were promoted to Spain's top flight following more than a decade in the second division after finishing second behind Real Sociedad last season.
Second division Real Betis and Segunda B (third tier) Cadiz lodged formal complaints against Hercules in early August.
Hercules said in a statement earlier this month that suggestions the goalkeeper of rival club Cordoba had been paid to throw a match at the beginning of May which Hercules won 4-0 were false.