ORS § 40.280
A person upon whom ORS 40.225 to 40.295 confer a privilege against disclosure of the confidential matter or communication waives the privilege if the person or the person's predecessor while holder of the privilege voluntarily discloses or consents to disclosure of any significant part of the matter or communication. This section does not apply if the disclosure is itself a privileged communication. Voluntary disclosure does not occur with the mere commencement of litigation or, in the case of a deposition taken for the purpose of perpetuating testimony, until the offering of the deposition as evidence. Voluntary disclosure does not occur when representatives of the news media are allowed to attend executive sessions of the governing body of a public body as provided in ORS 192.660(4), or when representatives of the news media disclose information after the governing body has prohibited disclosure of the information under ORS 192.660(4). Voluntary disclosure does not occur when a public body, as defined in ORS 192.311, discloses information or records in response to a written request for public records made under ORS 192.311 to 192.478. Voluntary disclosure does occur, as to psychotherapists in the case of a mental or emotional condition and physicians in the case of a physical condition upon the holder's offering of any person as a witness who testifies as to the condition.
ORS 40.280