The Options Price Reporting Authority (OPRA) oversees the Securities Information Processor (SIP) that provides last sale information and current options quotations from a committee of participant exchanges.
In turn, this committee is designated as the Options Price Reporting Authority.
Current OPRA participants include: The Securities Industry Automation Corporation (SIAC) administers the Securities Information Processor (SIP) for OPRA.
The SIP gathers the last sale and quote information from each of the participant exchanges.
Data volume has increased dramatically since the early 1990s, as illustrated in the following table.