EVP Systems, by default for evaluations on or after April 30, 2017, uses “primary exchange” prices where available, meaning quotes from the exchange were a security is primarily traded. Most data available for free on-line comes from “composite” prices, meaning the average of all the exchanges were a security is traded.
We favor the primary price because doing so adheres closer to the government code. IRS Regulation § 20.2031-2 (b) 1 governs which prices are to be used for estate valuations and reads:
If the stocks or bonds are listed on more than one exchange, the records of the exchange where the stocks or bonds are principally dealt in should be employed if such records are available in a generally available listing or publication of general circulation. In the event that such records are not so available and such stocks or bonds are listed on a composite listing of combined exchanges available in a generally available listing or publication of general circulation, the records of such combined exchanges should be employed.
If you would rather see composite prices in your evaluation reports, EVP Systems can do that as well.
More information on the primary / composite distinction is available here.