Google error received: "Missing or invalid field: hiringOrganization". What does this mean and how can I resolve it?

Google error received: "Missing or invalid field: hiringOrganization". What does this mean and how can I resolve it?

The system adds the name of the website "SITENAME" by default to all the jobs published on your site. 

If you receive this error, please send support a link to the jobs with an error and we will investigate further.