24/7 Wall St.

Investors frequently get to see the analyst upgrades and Buy ratings from Wall Street firms. What investors often do not get to see is when analyst downgrade stocks to sell or to avoid. 24/7 Wall St. reviews many fresh research calls each and every day to find great ideas from value stocks to growth stocks to dividend stocks and we have broken out the negative analyst calls today. These are this Tuesday’s top analyst downgrades and cautious research notes from Wall Street.

Barrick Gold Corp. (NYSE: ABX) was downgraded to Hold from Buy at Stifel Nicolaus.

E.I. du Pont de Nemours and Co. (NYSE: DD), or DuPont, was downgraded to Neutral from Outperform by Macquarie

Gentex Corp. (NASDAQ: GNTX) was downgraded to Neutral from Outperform by R.W. Baird.

International Business Machines Corp. (NYSE: IBM) was downgraded to Neutral from Buy at Goldman Sachs.

Intuitive Surgical Inc. (NASDAQ: ISRG) was downgraded at multiple firms after lowering its second-quarter guidance, and shares are down almost 15% so far: downgraded to Hold at Canaccord Genuity, to Neutral from Buy at Goldman Sachs, to Market Perform at JMP Securities and to Market Perform at Raymond James. Several firms also lowered their price targets.

Quest Diagnostics Inc. (NYSE: DGX) was downgraded to Underweight from Equal Weight by Morgan Stanley.

Ryder Systems Inc. (NYSE: R) was downgraded to Hold from Buy at BB&T.

Wells Fargo & Co. (NYSE: WFC) was downgraded to Neutral from Positive based on valuation at Susquehanna ahead of its earnings report.

Here are the top analyst upgrades and positive calls for Monday.