Change notification obligations can render a filed notice invalid if changes materially affect competition after a hearing. Parties who have filed a combination notice must promptly inform the Commission of any changes to the notice; the Secretary will place such changes before the Commission within three working days. The Commission will assess the significance, may record the information, or-if the change may materially affect factors for determining an appreciable adverse effect on competition-after hearing and reasons, treat the notice as not valid; the Secretary will communicate such decisions within seven working days and refiling within thirty days incurs no extra fee.