When Guinness/Atkinson converted their two dividend builder mutual funds to ETFs
, they picked two symbols for their new SmartETFs
: ADIV and DIVS.
ADIV had not been previously used, but DIVS had been used by the defunct-since-2012 Russell Small Cap High Dividend Yield ETF
Previously used symbols may be easy to pronounce, familiar, or may evoke the investing approach used by the new ETF. While a memorable symbol may confer a marketing advantage, it does not provide a guarantee of sucess.
For example, ETFs that bit the dust last year include CHEP (value), KNOW (insider), TAWK (communications sector), and SEA (shipping sector).
In addition, when a previously used symbol is ‘resurrected’, some third-party ETF research/data providers (such as FactSet) may get confused, and may not - at least initially - accurately report info on a new ETF that uses a ‘resurrected’ symbol.
When you pick a symbol for your new ETF, see if you can come up with a symbol that has not been used before. 
Click on the links below, for example, and compare the results for ADIV vs DIVS.
 As of this writing, ETFDB.com currently identifies the DIVS symbol as the Russell Small Cap High Dividend Yield ETF
. FactSet/ETF.com does not currently recognize DIVS at all.
 ETF.com chronologically lists ETF closures
, going all the way back to 2008.