I’m not sure that’s quite the case sunpak. here’s what I think happens…
Mutual Funds: When a new investor buys 100 units of the fund, the fund manager has his traders go out and purchase more of the underlying positions that the mutual fund is replicating. When the investor sells 100 units, the mutual fund sells the underlying positions the fund is replicating. The physical sale of the underlying is a taxable event for the mutual fund.
ETF (warning this doens’t make sense at all). When an investors buys the ETF, the ETF fund manager will arrange a swap with dealers, market makers etc where the swap is the underyling position the ETF is trying to replicate and the dealer/market makers receive cash. When the investor sells from the ETF, the swap is closed and cash is returned.
“Unlike mutual funds, ETFs do not sell holdings in exchange for cash, which would trigger a taxable event. Instead, the ETFs undergo a creation and redemption process in which market makers, authorized participants or large institutional investors swap a basket of securities from the underlying benchmark index for ETF shares, or vice versa.
An authorized participant would borrow shares of stock from an underlying benchmark and put them in a trust to form a so-called creation unit of an ETF. The Trust would provide shares of the ETF that are legal claims on the shares held in the ETF. As such, the authorized participant exchanges the basket of stocks for ETF shares, which are then sold to the public as stocks in the open market.”
http://www.etftrends.com/2012/03/what-is-an-etf-part-4-in-kind-creations...