Seven people were killed and 58 others were injured when a powerful storm toppled onto a crowd who had gathered to watch the country duo "Sugarland" perform.
The Indiana Occupational Safety and Health Administration said that Mid-America Sound Corporation, the company that built the stage, appeared to be indifferent to safety standards. They were cited for three violations totaling $63,000.
"These three violations were classified as 'knowing,' and are the most serious classification that we can use," said Lori Torres, commissioner of the Indiana Department of Labor.
A local stage hands union was fined over $11,000 and the Indiana State Fair Commission was fined $6,300 for their roles in the deadly accident.
IOSHA also said that the commission received "inadequate" weather information and didn't have the right plan to evacuate the premises.
The report examined workplace violations, but it was not aimed at determining what caused the collapse.
ABC News contributed to this story.