FSST mainly invests in US companies that the fund adviser believes to have proven or improving sustainability practices. Evaluation of the companies impact characteristics may involve corporate engagement and its alignment with the United Nations Sustainable Development Goals using qualitative analysis as well as proprietary or third-party data. Their approach to sustainable investing not only considers ESG factors but fundamental ones as well, including financial conditions, industry positions, as well as market and economic conditions. Unlike other ETFs that disclose holdings on a daily basis, FSST publishes its full portfolio holdings monthly with a 30-day lag. A Tracking Basket Structure is in place which acts as a proxy portfolio and may include holdings from recent disclosures, other liquid ETFs as well as cash and cash equivalents in order to track the funds daily performance and facilitate arbitrage opportunities.