IUS offers two main distinctions in its exposure to stocks from large US firms. First, it ignores market cap as the primary means of determining whether a company is large or small. Instead, it ranks by fundamental metrics: revenue, operating cash flow, dividends & buybacks, and book value. Second, IUS screens for quality, using the current levels and historical growth of sales/assets. The fund is weighted by the same fundamental size metrics used in selection. As such, it will take a somewhat contrarian approach relative to cap-weighted funds: At rebalance, it will take profits from gainers and top up losers. The fund issuer, Invesco, also provides the index.