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Stocks were indicated lower on Monday after a week of rallying took the Dow Jones Industrial Average above 18,000 and took the S&P 500 up to nearly 2,100. Investors have shown over and over that they will buy stocks that offer value or that have been overlooked. 24/7 Wall St. reviews dozens of analyst research reports each morning of the week on the hunt for new investment and trading ideas for its readers. Some analyst reports cover stocks to buy, and others cover stocks to sell or avoid.

These are this Monday’s top analyst upgrades, downgrades and initiations seen from Wall Street research calls.

Ambarella Inc. (NASDAQ: AMBA) was downgraded to Underperform from Hold at Needham.

Gilead Sciences Inc. (NASDAQ: GILD) was raised to Overweight from Equal Weight with a $104 price target (versus a $93.79 close) at Morgan Stanley. Gilead was also named as a Top 10 Picks for 2015 by Barron’s this past weekend.

Halyard Health Inc. (NYSE: HYH) was started as Market Outperform with a $50 price target (versus a $41.71 close) at JMP Securities.

Inphi Corp. (NYSE: IPHI) was raised to Strong Buy from Buy with a $23 price target at Needham.

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MarkWest Energy Partners L.P. (NYSE: MWE) was raised to Overweight from Equal Weight and the price target was raised to $81 from $79 (versus a $66.62 close) at Stephens.

PNC Financial Services Group Inc. (NYSE: PNC) was started as Hold at Argus.

RF Micro Devices Inc. (NASDAQ: RFMD) was downgraded to Hold from Buy at Needham.

Skyworks Solutions Inc. (NASDAQ: SWKS) downgraded to Hold from Buy at Needham.

TriQuint Semiconductor Inc. (NASDAQ: TQNT) downgraded to Hold from Buy at Needham.

RigNet Inc. (NASDAQ: RNET) was started as Neutral at Macquarie.

Sonus Networks Inc. (NASDAQ: SONS) was started as Buy at Wunderlich.

This weekend we featured 13 recent analyst stocks to buy trading at or under $10.

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