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.

OpenTable, Inc. (OPEN) gets a higher grade this week, advancing from a C last week to a B. OpenTable provides free, real-time online restaurant reservations for diners through an online booking service. For more information, get Portfolio Grader’s complete analysis of OPEN stock.

Internap Corporation’s (INAP) ratings are looking better this week, moving up to a B from last week’s 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.