The Indiana Occupational Health and Safety Administration is partially blaming three organizations for the disaster that left seven people dead and dozens hurt.
The agency fined the State Fair Commission more than $6,000 for failing to have a severe weather plan in place and for not doing a proper safety check.
The local stagehands union was also cited and hit with an $11,000 fine.
But it was Mid-America Sound Corporation that got the heftiest fine: $63,000.
IOSHA said the company showed "plain indifference" to safety standards