These are the top analyst calls of upgrades, downgrades and initiations we have seen from Wall St. research calls this Friday morning.

Cerner Corp. (NASDAQ: CERN) cut to Equal Weight at Morgan Stanley.

FuelCell Energy Inc. (NASDAQ: FCEL) started as Market Perform at FBR.

Krispy Kreme Doughnuts Inc. (NYSE: KKD) started as Outperform at Wedbush Morgan.

GT Advanced Technologies Inc. (NASDAQ: GTAT) raised to Buy at Canaccord Genuity.

Groupon Inc. (NASDAQ: GRPN) cut to Underweight at Evercore.

Marvell Technology Group Ltd. (NASDAQ: MRVL) cut to Sector Perform at RBC.

McKesson Corp. (NYSE: MCK) cut to Equal Weight at Morgan Stanley.

Medtronic Inc. (NYSE: MDT) raised to Buy at Argus.

Molycorp Inc. (NYSE: MCP) cut to hold at boutique firm Dahlman Rose.

Phillips 66 (NYSE: PSX) started as Overweight at JPMorgan.

Tesoro Corporation (NYSE: TSO) started as Overweight at JPMorgan.

Viacom Inc. (NASDAQ: VIA) raised to Outperform at Wells Fargo.

Wellpoint Inc. (NYSE: WLP) cut to Equal Weight at Morgan Stanley.

JON C. OGG

Filed under: 24/7 Wall St. Wire, Analyst Calls Tagged: CERN, FCEL, GRPN, GTAT, KKD, MCK, MCP, MDT, MRVL, PSX, TSO, VIA, WLP