As the S&P 500 continues to trade near record highs, short interest appears to be on the rise.
According to data from FactSet, in the first half of July average short interest for S&P 500 stocks increased more than 5 percent, with over 55 percent of those companies seeing a spike in short interest.
Short interest measures the total number of shares of a security that have been sold short, expressed as a percent of total tradable shares.
Investors track short interest levels to gain a sense of where a stock might be headed, along with some insight into whether any positive news might force short traders to cover their positions, pushing stocks higher.