Stocks are challenging all-time highs and investors have to wonder which stocks are set to keep rising and which ones to sell. 24/7 Wall St. reviews many fresh research calls each morning, on the hunt for new ideas, 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.

BlackBerry Ltd.(NASDAQ: BBRY) was downgraded to Underperform from Sector Perform at CIBC. Keep in mind that BlackBerry’s deal is off, and it was also included on the top analyst upgrades on Tuesday as well. We believe that it is safe to expect many analyst changes in this stock this week.

Exlservice Holdings Inc. (NASDAQ: EXLS) is getting crushed after Travelers terminated its pact over a confidentiality breach. This one was downgraded to Underweight from Neutral at J.P. Morgan, downgraded to Market Perform from Outperform at Wells Fargo and downgraded to Perform from Outperform at Oppenheimer.

Kellogg Co. (NYSE: K) was downgraded to Hold from Buy, based on low visibility, by Deutsche Bank.

Mindray Medical International Ltd. (NYSE: MR) was started as Underperform at Credit Suisse.

Pearson PLC (NYSE: PSO) was downgraded to Neutral from Buy at Goldman Sachs.

Rovi Corp. (NASDAQ: ROVI) was downgraded to Sell from Neutral and the price target was cut to $15 (versus a $16.75 close) at Goldman Sachs.

Royal Bank of Scotland Group PLC (NYSE: RBS) was downgraded to Underperform from Neutral by BNP Paribas.

Siemens A.G. (NYSE: SI) was downgraded to Neutral from Buy at UBS.

Here are 10 serious reasons that Apple is selling off after earnings rather than rallying.