If you are looking for clues to tell you which stocks have a good chance of increasing in value, you might want to 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.

U.S. Gold (UXG) topped the insider-buying charts for the week ending March 4 as insiders snapped up 3,067,000 shares of company stock at a market value of $19,935,500. During the past six months, insiders have increased their overall holdings in the company by 30.97% and now own 21.13% of UXG stock.

Analyst upgrades:

• Toll Brothers (NYSE: TOL) was upgraded to Buy at Citigroup. The firm views the recent sell-off in home building stocks as a buying opportunity and thinks Toll Brothers offers the best risk/reward in its coverage universe. Citi keeps a $23 price target on the stock.
• Kellogg (NYSE: K) was upgraded to Buy from Hold at Citigroup following the Q3 results, as it believes the company's reduced spending and share buyback will serve as catalysts. The firm raised its price target on shares to $63 from $50.
• Rogers Communications (NYSE: RCI) and Telus (NYSE: TU) were upgraded to Outperform from Sector Perform at RBC Capital, which said the CRTC unexpectedly denied Globalive's wireless application. The analyst said Globalive was potentially the biggest of new wireless competitors and the decision removes a big threat to the group. Rogers price target was raised to $40 from $33; Telus to $44 from $36.
• Stanley (NYSE: SXE) was upgraded at Wells Fargo to Outperform from Market Perform after the company reported better-than-expected Q3 results and raised its FY10 guidance.
• Texas Instruments (NYSE: TXN) was upgraded at Bernstein to Outperform from Market Perform. The analyst believes Texas Instruments' core business earnings power is underappreciated and valuation is attractive. Target raised to $30 from $28.

• McAdams Wright expects Dendreon's (NASDAQ: DNDN) near-term momentum to continue but has long-term concerns that Street estimates are too high. The firm upgraded shares to Hold from Sell.
• JPMorgan upgraded Ameristar Casinos (NASDAQ: ASCA) to Overweight from Neutral to reflect valuation, potential catalysts from Colorado's easing gaming regulations, and the company's strong free cash flow. The firm raised its target on shares to $24 from $20.
• Citigroup upgraded Valspar (NYSE: VAL) to Hold from Sell after channel checks indicated paint demand is shifting to big-box retailers, the company's primary sales channel. The firm raised its target on shares to $22 from $19.
• Vulcan Materials (NYSE: VMC) was upgraded to Buy from Neutral at UBS.
• Altera (NASDAQ: ALTR) was raised to Outperform from Sector Perform at RBC Capital.
• Spectra Energy (NYSE: SEP) was upgraded to Neutral from Sell at Goldman.