Waive Eligibility for New Plan

When starting a new plan, must eligibility be waived for ALL employees?  Or can we say "eligibility is waived for ALL full time employees"?  However full time is defined.

No, not all employees. The plan document should have some provisions to add for waiving eligibility, like all employees employed on a certain date or work 83.33 hours per month. Must be very careful though on the options and if you want some out of box provisions, always ask the vendor and/or an attorney if they are kosher.