4. Upon request by the Disclosing Party, the Receiving Party shall immediately return to the Disclosing Party all documents, samples, and other materials in any form containing or reflecting any Information and will not retain any copies, extracts, or other reproductions, in whole or in part, of such written material, except that one archival copy to be kept confidential may be retained for proposed of assuring compliance with this Agreement only. All other documents, memoranda, notes and other writings whatsoever prepared by Receiving Party or its advisors based on or related to the Information shall be destroyed and such destruction shall promptly be certified in writing to the Disclosing Party, except that nothing in this paragraph shall require the return or destruction of laboratory notebooks maintained in the ordinary course of business nor of records required by law to be maintained. Notwithstanding the return, retention or destruction of the Information, Receiving Party will continue to be bound by its obligations of confidentiality and other obligations hereunder.