Stocks making the biggest moves midday: Instacart, Disney, Planet Fitness, Rackspace and more

cnbc.com:

Check out the companies making headlines in midday trading.

Starbucks — Shares fell 2% in midday trading following a downgrade to market perform from TD Cowen. Analyst Andrew Charles noted concern over macroeconomic headwinds in China that could hit consumer spending at Starbucks stores.

Instacart — The grocery delivery stock roared out the gates as it debuted on the public market midday Tuesday. Shares popped about 35%. The company had priced its initial public offering at $30 a share Monday, the high end of the expected $28 to $30 range.

Disney — The entertainment stock slumped more than 3% after Disney revealed that it plans to nearly double its spending on its parks and cruises businesses to roughly $60 billion.

Super Micro Computer — Stock in the computer technology company climbed close to 2% after Barclays initiated coverage of shares at an overweight rating. Analyst George Wang said the stock could benefit from a still-growing artificial investment trend.

Deere — The industrial stock fell nearly 3% after Evercore downgraded the shares to in line from outperform. The Wall Street firm said the trends and early color from its contacts suggest revenue declines and agriculture production cuts for Deere's next fiscal year.

Planet Fitness — Shares of the gym franchise slid 5% after JPMorgan downgraded the stock to a neutral rating from overweight. The investment bank cited the recent surprise ousting of CEO Chris Rondeau and an uncertain macroeconomic future as reasons for the downgrade.

Arm Holdings — Shares of the semiconductor company, which recently went public, dropped 4%. Redburn Atlantic Equities initiated coverage of the company as neutral and said it is overvalued right now.

Array Technologies — The solar