If at first you don’t succeed, skydiving is not for you
Long ago, stock trades were reported over ticker tape, and one type of manipulation was called “painting the tape.” Traders would enter orders to give the appearance of activity in a stock to entice others to buy shares, thus pushing the price higher.
Today, a slightly more sophisticated scheme is called “banging the close,” in which transactions are made in one market at the end of the day to benefit a trader’s positions in another market, say derivatives. Same scheme, different means. […]
The growth of high-frequency trading firms and transactions executed on alternative trading systems, called dark pools, have made it more difficult to police potential manipulative conduct. High-frequency traders buy and sell millions of financial instruments but rarely hold a position for more than a day. While such trading provides greater liquidity to the markets, helping to lower costs for all investors, it can also offer new opportunities for manipulating prices. […]
Manipulation can also involve benchmark indexes, which are incorporated into a wide variety of transactions, including mortgage interest rates. When an index relies on reports provided by rival market participants, the temptation to furnish false information to affect its value can be powerful because a small shift in value can affect billions of dollars. Several large banks have already paid billions in penalties for manipulation of the London interbank offered rate, or Libor, and investigations are gaining steam into how currency prices were reported in the foreign exchange markets.