The Scotsman was accused by The Telegraph of offering advice on how to bribe club officials.
Undercover reporters secretly filmed a discussion with Black, which prompted Southampton to launch their own probe into the allegations.
On Thursday, the Premier League outfit confirmed via their official website that they have not found any evidence of "wrongdoing" and consider the matter closed.
A statement read: "Despite numerous requests to provide the club with any evidence relating to the allegation against Mr Black, none has been forthcoming.
"There is no evidence of any wrongdoing, and as such, the club now considers the matter closed. Eric Black retains the full support of Southampton Football Club."
Black joined the Saints in June this year to work alongside manager Claude Puel.