Too bad it isn't opposite day in the world of hedge funds.

A new note from Bank of America Merrill Lynch analysts Jue Xiong and Stephen Suttmeier suggests that if a hedge fund says it's bullish on a stock, you might do well to sell it. The top 20 stocks most beloved by hedge funds underperformed the broader S&P 500 index in January, according to BofAML data. At the same time, the 100 that hedge funds are most short were up 4.59 percent in February, outperforming their top 100 longs by the most since BofAML began tracking the data some five years ago.

Here's a chart from Bank of America's note showing the performance of the top 100 longs, top 100 shorts, and the core holdings of large mutual funds since the start of the year.

This is a similar theme to a note from Goldman Sachs Group Inc. last month that showed the stocks hedge funds love the most are underperforming the broader market. One thing that might be to blame is a rush to the exits by such funds, which could cause a so-called short squeeze that pushes share prices higher.

"We find that for a typical hedge fund, the top 20 stock positions make up roughly 83.1 percent of their long equity portfolio," the BofAML analysts said. "The biggest funds tend to be more diversified, with the 20 largest stock holdings making up approximately 70.6 percent of their portfolio."

So what are some of these top holdings? According to the BofAML note, some of the companies that make up the top 20 longs include Allergan plc, Alphabet, Inc., Facebook Inc., Apple Inc., Amazon.com Inc., Yahoo! Inc., and Citigroup Inc. Companies that were added to the top 20 during the quarter include EMC Corporation, Synchrony Financial, and McDonald's Corporation. Names taken off of the list include Broadcom Corporation, American International Group Inc., and eBay Inc.

When it comes to the stocks hedgies are shorting the most, Tesla Motors Inc., Caterpillar Inc., the Walt Disney Company, Deere & Company, and United Technologies Corporation take the top five spots.