iShares Core S&P 500 ETF USD Dist. tracks the S&P 500 by holding the actual stocks of the 500 largest U.S. companies, so its portfolio is made up of broad large‑cap U.S. equities across major sectors (technology, healthcare, financials, consumer, etc.), reflecting established U.S.-based multinationals and aiming to replicate the index’s sector and company weightings.