Institutional Investments Boost PRF Fund Holdings Invesco FTSE RAFI US 1000 ETF (PRF) saw increased institutional investments, with Oppenheimer & Co. acquiring $205,000 worth of shares. The stock, trading at $40.92, has a 1-year range of $36.36 to $43.01. PRF tracks a fundamental index of 1,000 large U.S. companies, appealing to long-term investors.3