Google and IAC are at odds over what Google calls misleading marketing practices, putting a lucrative deal at stake.

IAC/InterActive Corp. offers a number of extensions for Google’s popular Chrome web browser. IAC markets the extensions as useful tools to make users’ lives easier. These can include manuals for various tools, saving users from searching for them. Other extensions provide easy access to government forms, or daily Bible quotes.

According to the Wall Street Journal, however, some of IAC’s extensions do not perform as advertised. Even worse, the Chrome safety and trust team found that some extensions steer users toward more ads. According to documents the WSJ gained access to, the behavior was egregious enough the Chrome team recommended “immediate removal and deactivation” of the company’s extensions from the Chrome store.

IAC’s chairman, Barry Diller, has said doing so would be devastating to IAC’s business. That hasn’t stopped Google from removing a number of the extensions, although the company told Reuters it is still working with IAC and reviewing their remaining extensions.

Part of Google’s concern as it moves forward is the need to juggle appearances with the security of its users. The company is already under extensive scrutiny over antitrust and anticompetitive concerns. As a result, any action Google takes need to be above reproach and not add to the scrutiny it’s already under.