Some short-seller bets looked surprising in coronavirus crash

March 13 (Reuters) - Some short-seller favorites this week as the U.S. stock market nosedived on coronavirus fears looked counter-intuitive because the companies might benefit from the crisis, notably 3M Co, Facebook Inc and Alphabet Inc, according to S3 Partners.

Short sellers sell borrowed shares in the hope of buying them back at a cheaper price and pocketing the difference.

Short sellers built their largest dollar bets in biopharmaceutical company Abbvie this week to Thursday, according to S3, but even more notable was the popularity of 3M, which makes everything from Post-it notes to protective masks.

Although mask demand surged as people looked frantically for protection against infection from the coronavirus, 3M saw the eighth biggest increase in the dollar amount of its shares sold short this week, with an additional $245.75 million more of its shares borrowed to sell, the firm’s data showed.

Facebook was also in high demand with shorts with an additional $244.9 million of its shares sold short in the same timeframe, making it the ninth most popular among shorts. The two classes of shares in Google parent Alphabet were also in demand, making them the 11th and 18th most popular stocks to borrow. In Alphabet’s C shares, $234.3 million worth were sold short, while $184.1 million of its A shares were borrowed to sell.

“Those are things I wouldn’t have thought would be on this list because their products and services are high demand,” said S3 managing director Ihor Dusaniwsky, noting that as more people stayed home with a view to protecting against the virus’ spread, it would seem likely that they would use online services such as Facebook and Google more than ever.

By Friday’s close 3M shares were 10.9% below where they were before the broader market sell-off began on Feb. 20. In comparison the S&P 500 benchmark index on Friday was 19.9% below its Feb. 19 record. Facebook fell 21.7% in the same timeframe, and Alphabet’s A shares have fallen more than 20%.

Abbvie saw an increase in short selling to the tune of $402.7 million worth of shares, according to S3.

At No. 2 was MGM Resorts with $342.4 million worth of new short-selling, followed by Exxon Mobil Corp.

The stocks with the biggest decline in the value of short positions in the last week were Digital Realty, AT&T Inc and Lockheed Martin Corp.

According to data from IHS Markit, the most shorted U.S. stocks were the biggest decliners so far this month.

Out of a group of 3,000 U.S. equities, the average stock fell 24.9% from the start of March to the close of trading on Thursday, but the stocks with most shares shorted fell 28.4% in the same timeframe, according to Samuel Pierson, director of securities finance at IHS Markit. (Reporting by Sinéad Carew; Editing by Alden Bentley and Leslie Adler)