Oregon Revised Statutes Mineral Resources § 517.060

If at any time an individual who has located a mining claim within the meaning of ORS 517.010 or 517.044, or the assigns of the individual, apprehends that the original notice of location of the mining claim was defective, erroneous, or that the requirements of the law had not been complied with before the filing of the notice, such locator or assigns may post and record in the manner now provided by law, an amended notice of the location which shall relate back to the date of the original location. However, the posting and recording of the amended notice of location shall not interfere with the existing rights of others at the time of posting the amended notice.