PKW holds stocks in firms that have purchased significant chunks of their own stock. The idea is simple: A firm's own managers know the best valuation of its stock, and if it's undervalued, they'll buy it up, assuming they have the cash. There are criticisms of this approach: perhaps the firm has nothing better to do with its earnings because it's a cash cow with no growth opportunities. Buybacks also buoy earnings-per-share without adding enterprise value. But for investors who want access to the buyback trend, PKW provides easy access, though it's worth noting that its thesis still yields a fund that looks like the broader market in some ways. Unlike some niche peer ETFs, the fund doesn't reach far down the market-cap spectrum. Instead, large caps dominate PKW's small basket. The Fund and the Index are reconstituted annually and rebalanced quarterly.