Stocks have mostly been indicated to open in positive territory in the United States on Tuesday after a three-day weekend. Last week saw handy gains, and oil briefly hit $50 again. It seems that the “Sell in May and go away” mantra did not live up to snuff this year, but that saying really applies to the summer months being down or quiet.

Investors have proved over and over that they will buy the big market dips. 24/7 Wall St. reviews dozens of analyst research reports each morning of the week. The goal is to find new investing and trading ideas for our readers. Some analyst reports cover stocks to buy, and other reports feature stocks to sell or to avoid.

These are the top analyst upgrades, downgrades and initiations seen on Tuesday morning:

Cliffs Natural Resources Inc. (NYSE: CLF) was raised to Overweight from Neutral with a $7 price target (versus a $3.07 prior close) at JPMorgan. It has a consensus analyst price target of $2.86 and a 52-week trading range of $1.20 to $5.83.

Deere & Co. (NYSE: DE) was raised to Buy from Neutral with a $94 price target (versus an $80.50 close) at UBS. Its consensus price target is $76.39, and it has a 52-week range of $70.16 to $98.23.

Lockheed Martin Corp. (NYSE: LMT) was downgraded to Hold from Buy with a $260 price target (versus a $240.09 close) at Berenberg. The consensus price target is $243.06, and the 52-week range is $181.91 to $245.37.

Micron Technology Inc. (NASDAQ: MU) was raised to Outperform from Neutral and the price target was raised to $18 from $12 (versus a $12.31 close) at R.W. Baird. The consensus price target is $13.48. The 52-week range is $9.31 to $28.53.

Zillow Group Inc. (NASDAQ: ZG) was started as Neutral with a $30 price target (versus a $29.18 close) at Mizuho Securities. The 52-week range is $16.45 to $35.47. The consensus price target is $29.79.

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