For the current week, the overall ratings of four Software stocks are worse, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

This week, SRS Labs (NASDAQ:SRSL) falls to a D (“sell”), worse than last week’s grade of C (“hold”). SRS Labs develops and licenses audio and voice enhancement technologies. In Portfolio Grader’s specific subcategories of Earnings Growth and Margin Growth, SRSL also gets F’s. For a full analysis of SRSL stock, visit Portfolio Grader.

TeleNav, Inc. (NASDAQ:TNAV) experiences a ratings drop this week, going from last week’s C to a D. TeleNav provides location-based solutions. The stock gets F’s in Earnings Growth, Earnings Momentum, and Margin Growth. To get an in-depth look at TNAV, get Portfolio Grader’s complete analysis of TNAV stock.

This week, Red Hat, Inc.’s (NYSE:RHT) rating worsens to a D from the company’s C rating a week ago. Red Hat provides open source software solutions that customers are allowed to update, monitor and manage. The stock price has fallen 10.1% over the past month, worse than the 1.7% decrease the S&P 500 has seen over the same period of time. The stock’s trailing PE Ratio is 56.90. For a full analysis of RHT stock, visit Portfolio Grader.

This week, Taomee Holdings Ltd. Sponsored ADR (NYSE:TAOM) drops from a C to a D rating. Taomee Holdings produces children’s entertainment. The stock gets F’s in Earnings Surprise and Margin Growth. The stock currently has a trailing PE Ratio of 53.50. For more information, get Portfolio Grader’s complete analysis of TAOM stock.

Louis Navellier’s proprietary Portfolio Grader stock ranking system assesses roughly 5,000 companies every week based on a number of fundamental and quantitative measures. Stocks are given a letter grade based on their results — with A being “strong buy,” and F being “strong sell.” Explore the tool here.