}
	if retainDateStr, ok := lkMap.Lookup(xhttp.AmzObjectLockRetainUntilDate); ok {
		rdate, err := amztime.ISO8601Parse(retainDateStr)
		if err != nil {
			return putOpts, false, err
		}
		putOpts.RetainUntilDate = rdate
		// set retention timestamp in opts
		retTimestamp := objInfo.ModTime
		if retainTmstampStr, ok := objInfo.UserDefined[ReservedMetadataPrefixLower+ObjectLockRetentionTimestamp]; ok {

				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockMode)] = string(objRetention.Mode)
				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockRetainUntilDate)] = amztime.ISO8601Format(objRetention.RetainUntilDate.UTC())
			} else {
				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockMode)] = ""
				oi.UserDefined[strings.ToLower(xhttp.AmzObjectLockRetainUntilDate)] = ""
			}