These are some of the top analyst upgrades, downgrades and initiations seen from Wall St. research calls this Wednesday.

Akorn Inc. (NASDAQ: AKRX) started as Buy with $18 target at BofA/ML.

Broadcom Corp. (NASDAQ: BRCM) reiterated Buy with $46 target at Argus.

Carnival Corp. (NYSE: CCL) cut to Hold at Jefferies and raised to Buy at S&P Equity Research.

Chesapeake Energy Corp. (NYSE: CHK) cut to Hold at Stifel Nicolaus.

China Telecom Corp. Ltd. (NYSE: CHA) cut to Neutral at Credit Suisse.

Electronic Arts Inc. (NASDAQ: EA) cut to Neutral at BofA/ML.

Facebook Inc. (NASDAQ: FB) reiterated Neutral with $23 target at BofA/ML.

GT Advanced Technologies Inc. (NASDAQ: GTAT) cut to Hold at Canaccord Genuity.

L-3 Communications Holdings Inc. (NYSE: LLL) named as Bear of the Day at Zacks.

MarketAxess Holdings Inc.(NASDAQ: MKTX) cut to Underperform with $28 target at Credit Suisse.

Marvell Technology Group Ltd. (NASDAQ: MRVL) cut to Hold at Canaccord Genuity.

Republic Services Inc. (NYSE: RSG) started as Hold at KeyBanc.

SanDisk Corp. (NASDAQ: SNDK) cut to Market Perform at JMP Securities.

Texas Instruments Inc. (NASDAQ: TXN) cut to Perform at Oppenheimer.

Transocean Ltd. (NYSE: RIG) raised to Neutral from Sell at Goldman Sachs.

Waste Management Inc. (NYSE: WM) started as Hold at KeyBanc.

Western Refining Inc. (NYSE: WNR) named as Bull of the Day at Zacks.

JON C. OGG