In October, Tony LeCleir was struck by a forklift at the distribution center in Milan. He died in November.
OSHA inspectors found there was not enough space for operators to move equipment safely and that "traffic regulations" were not enforced at the center.
The agency designated all three citations as "serious." Deere was given a penalty of about $16,000 per citation.
According to an OSHA representative, Deere filed a notice to contest the citations.
It will first try to resolve the citations with OSHA. If the case is not resolved, it will be heard by an administrative law judge with the Occupational Safety and Health Review Commission. The commission is a separate agency from OSHA.
Because the case in now in litigation, OSHA says it's unable to comment any further.
John Deere did not immediately respond to requests for comment.