The ratings of 3 Software stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

salesforce.com, inc. (CRM) gets weaker ratings this week as last week’s C drops to a D. Salesforce.com, inc. offers businesses a technology platform for Internet-based computing, storage, and connectivity solutions. For more information, get Portfolio Grader’s complete analysis of CRM stock.

MIND C.T.I. Ltd. (MNDO) slips from a D to a F this week. MIND C.T.I. Ltd. is a developer, manufacturer, and marketer of real-time and off-line billing and customer care software for communication providers. The company also gets F’s in sales growth. For more information, get Portfolio Grader’s complete analysis of MNDO stock.

Sky-mobi Ltd. Sponsored ADR (MOBI) experiences a ratings drop this week, going from last week’s D to a F. Sky-mobi Ltd. Sponsored ADR engages in the operation of a mobile application platform embedded on mobile phones to provide mobile application store and services in the People’s Republic of China. The company also gets F’s in sales growth and earnings growth. For more information, get Portfolio Grader’s complete analysis of MOBI 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.