// set retention timestamp in opts
		retTimestamp := objInfo.ModTime
		if retainTmstampStr, ok := objInfo.UserDefined[ReservedMetadataPrefixLower+ObjectLockRetentionTimestamp]; ok {
			retTimestamp, err = time.Parse(time.RFC3339Nano, retainTmstampStr)
			if err != nil {
				return putOpts, false, err
			}
		}
		putOpts.Internal.RetentionTimestamp = retTimestamp
	}