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Because stock tickers can vary from source to source, PropReports attempts to gather complete security information directly from your providing DMA platform or clearing firm. If complete information is provided by one of your DMA platforms platform(s) or clearing firmsfirm(s), PropReports will store gather that information and store it as the Security Master.
If we are unable to gather complete information for a security via your DMA platform or clearing firm, the first time an unknown security is traded and your data is uploaded into your instance, we will attempt to fetch the securities information from a central market data server which aggregates the data from multiple vendors.
Below is a screenshot of the security "QQQ". You can see that the security information considerably differs from source to source. 
To view a securities complete security's current information, navigate to the Audit > Symbols page and type in a symbolsecurity.
Instrument Timeline
PropReports records and maintains a timeline of all changes done made to security information (e.g. a listing exchange or a company name change). It is important to note that changes will effect any fee plan that calls the exchange code or tape, etc. The plans that are effected will apply the changes and recompute all data from the date the change occurred externally to the security, not from the date the plan was updated in PropReports.
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To view your market data timeline for a security, navigate to he the Audit > Symbols page, type in a security and click the Edit link.
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To view incomplete symbols, navigate to the Audit >Symbols page and search for "Incomplete". All incomplete securities appear with a red background, as seen in the screenshot below.
Material Fields
PropReports considers a field to be "material when " when a change made to it requires your instance to complete a recompute of all trade fees. For example, changing a security's CUSIP does not trigger a recompute, whereas changing the multiplier of a security would, as it can affect because the change can effect a trader's P/L.
Below are material fields that will trigger a recompute of all trade fees if altered:
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Note: you may overwrite merged data manually by editing the Security. To do this, navigate to the Audit > Symbols page and click Edit under Action.