This week, four internet and web service stocks are improving their overall rating on Portfolio Grader. Each of these rates an “A” (“strong buy”) or “B” overall (“buy”).

Commtouch Software Ltd (CTCH) ups its rating to a B (“buy”) this week after earning a C (“hold”) in the week before. Commtouch Software provides messaging, antivirus, and Web security solutions to OEM customers, enterprises, and service providers primarily in Israel, North America, Europe, and Asia. In Portfolio Grader’s specific subcategory of Sales Growth, CTCH also gets an A. For more information, get Portfolio Grader’s complete analysis of CTCH stock.

Google Inc. Class C (GOOG) is seeing ratings go up from a C last week to a B this week. Google is a global technology company that provides web-based search and advertising services. For more information, get Portfolio Grader’s complete analysis of GOOG stock.

Internap Network Services Corporation (INAP) earns a B this week, jumping up from last week’s grade of C. Internap Network Services provides a broad range of scalable information technology infrastructure services for enterprises. For more information, get Portfolio Grader’s complete analysis of INAP stock.

This week, Bitauto Holdings Ltd. Sponsored ADR (BITA) is showing good progress as the company’s rating jumps from a B (“buy”) last week to an A (“strong buy”). Bitauto provides Internet content and marketing services for the automotive industry, primarily in the People’’s Republic of China. For more information, get Portfolio Grader’s complete analysis of BITA 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.