The ratings of 8 Internet Software & Services stocks are down this week, according to the Portfolio Grader database. Each of these rates a “D” (“sell”) or “F” overall (“strong sell”).

Autohome, Inc. Sponsored ADR Class A (ATHM) slips from a C to a D this week. For more information, get Portfolio Grader’s complete analysis of ATHM stock.

Bitauto Holdings Ltd. Sponsored ADR (BITA) declines this week from a D to a F. Bitauto Holdings Ltd. Sponsored ADR provides Internet content and marketing services for the automotive industry, primarily in the People’’s Republic of China. The company also gets F’s in operating margin growth, earnings growth, and earnings momentum. For more information, get Portfolio Grader’s complete analysis of BITA stock.

Slipping from a C to a D rating, Zillow Group, Inc. Class A (ZG) takes a hit this week. For more information, get Portfolio Grader’s complete analysis of ZG stock.

This is a rough week for GrubHub, Inc. (GRUB). The company’s rating falls to D from the previous week’s C. The company also gets F’s in earnings momentum. For more information, get Portfolio Grader’s complete analysis of GRUB stock.

This week, United Online, Inc.’s (UNTD) rating worsens to a D from the company’s C rating a week ago. United Online, Inc. provides consumer products and services over the Internet. The company also gets F’s in earnings revisions and earnings momentum. For more information, get Portfolio Grader’s complete analysis of UNTD stock.

This week, Travelzoo Inc. (TZOO) drops from a C to a D rating. Travelzoo Inc. is an Internet media company that publishes travel and entertainment deals from travel and entertainment companies, and local businesses in North America, Europe, and the Asia Pacific. For more information, get Portfolio Grader’s complete analysis of TZOO stock.

TheStreet, Inc. (TST) gets weaker ratings this week as last week’s C drops to a D. TheStreet, Inc. is a digital financial media company that provides subscription-based and advertising-supported content and tools through a range of online platforms. For more information, get Portfolio Grader’s complete analysis of TST stock.

iPass Inc. (IPAS) experiences a ratings drop this week, going from last week’s C to a D. IPass Inc. offers enterprise mobility services on a global basis by providing services that simply, smartly and openly facilitate network access from mobile devices while providing the enterprise with visibility and control over their mobile ecosystem. The company also gets F’s in sales growth, return on equity, and free cash flow. For more information, get Portfolio Grader’s complete analysis of IPAS 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.