Stop getting invites for shared calendar

Someone in my team is incorrectly getting meeting invites for each new meeting that is created on a shared calendar for which he is a delegate, but not the owner. The shared calendar is a Google Calendar that is part of a Google Apps business account, and is being synced to Mac Calendar as a CalDAV account. Furthermore, there are other individuals that are also setup as delegates for the same calendar, who are not receiving meeting invites for this calendar. Does anyone know why this would be happening, and how to fix it so that this person no longer receieves invites for the shared calendar?