what do you mean?...you can access in a SavedSearch, the fields of a certain record, referred in the record on which you search.
in your case, you can have in the filters, the "Attendee Fields..."; it shall be in the list of filter-options, towards the end, when you can have the access to all the fields of all the records, which are referred in the Event-record.
so there(in the "Attendee Fields..."), you can pick for the criteria, any field which will have a specific value only for the companies, so then you will exclude all the attendees with this "mark".
in case you really cannot find such field, you go to the contact-record and you create a new custom field(a checkbox, for example), where you make a default value=checked, in case it is for "a company"...then you use that custom field as your "mark"