US TV
A report in The New York Times claimed that corporate sponsor AT&T helped sway voting for Allen by handing out phones with free text-messaging at parties supporting the singer in Arkansas.
The newspaper alleged that AT&T showed people how to "power text" and cast ten votes at once for their favourite singer, which breaches Idol rules.
In a statement, Fox and producers 19 Entertainment and FremantleMedia rubbished rumours of vote-rigging and favouritism.
"Fox and the producers of American Idol are absolutely certain that the results of this competition are fair, accurate and verified," they said.
"Kris Allen is, without a doubt, the American Idol. We have an independent third-party monitoring procedure in place to ensure the integrity of the voting process.
"In no way did any individuals unfairly influence the outcome of the competition."
Allen was the surprise victor over bookmakers' favourite Adam Lambert in last week's final.
Tube Talk
'Simpsons' ultimate countdown (15-11)The countdown of the greatest Simpsons episodes continues.
2012-13 Season
Katie Cassidy cast in The CW's 'Arrow'Katie Cassidy will star alongside Stephen Amell in The CW's Arrow.
US TV Interviews
Debby Ryan talks Disney's 'Jessie'The Suite Life's Debby Ryan stars in new Disney Channel comedy Jessie.
US TV Ratings
'Cougar Town' returns to ABC with 4.8mAll five major networks were down on Valentine's Day, with ABC suffering the most.
