Block Positioner
  
A block positioner is a type of trader who buys a large number of securities (cleverly named a block) from an investor in order to make a profit. She usually uses short sales to reduce the risk, and to try to sell the shares quickly.
Let’s say Jane Trader has done her research and believes that the price of Take A Risk, Inc. will go down. So she borrows the securities, sells them, and then buys them back at a lower price in order to pay back the loan. For large blocks of securities, she had better be right.
Anyone involved in block positioning has to register with the Securities and Exchange Commission (SEC), and have a minimum of $1 million on hand to cover any losses. So...re-count that money in your wallet before getting your new business cards printed.