U.S. stock futures are lower this morning, as oil prices continued to surge. Futures on the Dow Jones Industrial Average dropped 46 points to 12,048 and S&P 500 stock futures fell 7.50 points to 1,298. Nasdaq 100 futures declined 14.50 points to 2,289.

Negative sentiment ruled the European markets today. While STOXX Europe 600 Index has dropped 0.71%, London's FTSE 100 Index moved down 0.47%.

Most Asian markets ended lower, with Japan's Nikkei Stock Average dropping 1.19%, Australia's S&P/ASX 200 dropping 0.70% and China's Shanghai Composite gaining 0.56%.

If you are looking for clues telling you which stocks have a good chance of increasing in value, you might want consider watching what insiders are doing. After all, talk is cheap, but when insiders put their own money on the line, you should sit up and take note.

GTx Inc. (GTXI) topped the insider-buying charts for the week ending July 9 as insiders snapped up 5,467,860 shares of company stock at a market value of $15,310,008. During the past six months, insiders have increased their overall holdings in the company by 2.72% and now own 71.44% of GTXI stock.

Analyst upgrades:

• Thomas Weisel upgraded SanDisk (NASDAQ: SNDK) to Overweight from Market Weight due to accelerating manufacturing cost declines, potential NAND flash sourcing upside at Toshiba (OTC: TOSBF) and Samsung and an increase in 2H09 demand.
  
• Oppenheimer upgraded Quality Systems (NASDAQ: QSII) to Perform from Underperform to reflect potential benefits from the stimulus package and channel checks that indicated IT budgets are stabilizing. The firm raised its target price on shares to $54 from $40.
  
• RBC Capital upgraded OSI Pharmaceuticals (NASDAQ: OSIP) to Outperform from Sector Perform following positive Tarceva survey results and cites valuation.
• Marriott (NYSE: MAR) was upgraded to Outperform from Market Perform at JMP Securities.
  
• Grainger (NYSE: GWW) was upgraded to Buy from Neutral at BofA/Merrill.
  
• Duncan Energy Partners (NASDAQ: DEP) was upgraded to Buy from Neutral at UBS.

MORE NOTEWORTHY: InterMune, Inc (ITMN), Riverbed Technology, Inc (RVBD), Credence Systems Corp (CMOS) and MWI Veterinary Supply, Inc (MWIV) were today's more notable initiations:

• American Technology started InterMune Inc (NASDAQ: ITMN) with a Buy rating and $29 target as the firm believes the recent share weakness in InterMune provides a buying opportunity. The firm expects significant news flow from the ITMN-191 program over the next 12 months to provide positive catalysts to shares.

• Pacific Crest initiated Riverbed Technology Inc (NASDAQ: RVBD) with an Underperform rating and $22 target, citing valuation.

• Credit Suisse started Credence Systems (NASDAQ: CMOS) with an Underperform rating and $3 target.

• JP Morgan started MWI Veterinary (NASDAQ: MWIV) with an Overweight rating, saying industry fundamentals are favorable and MWIV's growth prospects are strong.

OTHER INITIATIONS:

• UBS & Merrill Lynch both started Duncan Energy Partners (NYSE: DEP) with a Neutral rating.

• Employers Holdings, Inc (NYSE: EIG) was initiated with an Equal-Weight rating at Morgan Stanley.

• Needham initiated Cascade Microtech, Inc (NASDAQ: CSCD) with a Buy rating and $18 target.

• Credit Suisse assumed coverage of Teradyne, Inc (NYSE: TER) and Amkor Technology (NASDAQ: AMKR) with a Neutral rating and $17 target.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).