Analysts have lowered their ratings this morning on drilling companies Hercules Offshore, Inc. (HERO - 3.45) and Patterson-UTI Energy, Inc. (PTEN - 14.08) and semiconductor name Rambus (RMBS - 6.09). Here's a quick roundup of today's bearish brokerage notes.

• HERO was cut to "market perform" from "outperform" at Raymond James, who adjusted its rating on a number of oil-industry stocks this morning. The mighty have certainly fallen, as HERO is down 22% in 2012 and off 34% during the last 52 weeks. And while the shares have underperformed the S&P 500 Index (SPX) by more than 31% in the past three months, six of the 13 brokers following the stock have named it a "buy" or "strong buy." Retail investors are less optimistic, lifting HERO short interest by 24% in the last month, leaving 9.2% of the stock's float sold on the short side.
  
  
• The Raymond James hammer also fell on PTEN today, as the stock's rating was lowered to "outperform" from "strong buy." Since peaking last July near the $35 level, PTEN has been in a slow downtrend, nearly shedding half its value in the last 52 weeks. Year-to-date, the stock is off 30%. While option speculators have crowded the bearish bandwagon, boosting the equity's Schaeffer's put/call open interest ratio (SOIR) to 1.84 (four percentage points shy of an annual peak), just over half of the 19 analysts following the stock rank it a "buy" or better.
  
  
• RMBS was lowered to "neutral" from "overweight" at JPMorgan this morning, as the broker said it can't find a clear reason for the stock's 45% advance from its May 18 low. The firm did not adjust its earnings estimates or 12-month price target of $6.50. Despite the stock's recent boost higher – which lifted it beyond its 80-day moving average for the first time since November – the shares are still off more than 19% in 2012. Just two brokers currently follow the stock, awarding one "neutral" and one "strong buy."