ARKK and ARKW. for there to be a wash sale they would have to be substantially identical, unfortunately, there is no absolute definition in the tax law or court cases to say whether that's the case.
if the security has a CUSIP number, then it's subject to wash-sale rules. In addition, selling a stock at a loss and then buying an option on that same stock will trigger the wash-sale rule.
ETFs and mutual funds present investors a different set of challenges. Switching from one ETF to an identical ETF offered by another company could trigger a wash-sale. There are ways around this problem. For instance, an investor holding an ETF indexed to the S&P 500 at a loss might consider switching to an ETF or mutual fund that is indexed to a different set of securities, such as the Russell 1000 or Dow Jones Industrial Average.
The main difference between ARKK vs ARKW is, ARKK invests across different innovation sectors, such as genomic revolution, industrial innovation, fintech innovation and the next generation of internet innovation. ARKW is more focused on next generation of internet innovation such as big data, IoT and E-commerce.
essentially they would be investing in different companies
a stock and an ETF are not identical - the first is just a stock the second is a basket of stocks. if wash sales rules were applied to this situation it would create enormous reporting problems. personally, I have bought stock A which is in ETF B and sold A at a loss and bought B within 30 days and never had a wash sale problem
one thing to watch out for is If you have a taxable account and an IRA. you sell at a loss in the taxable account and within 30 days buy in your IRA . you have a wash sale and the loss in taxable account disappears - you never get the benefit when you sell the wash sale loss in your regular a/c
