Earlier this month, the European Comission told Google that it had to improve its settlement terms in an antitrust investigation over its search practices or face charges. As part of its standard practice in an Article 9 procedure - which leads to a commitments decision - and in response to a pre-rejection letters sent to Google before the summer, twenty formal complainants have given the European competition authority "fresh evidence and solid arguments" against several aspects of the latest proposals put forward by Google.

Article 9 of Regulation 1/2003 provides for companies to make commitments that are binding if accepted, to meet the competition concerns of the commission.

"At the beginning of the month, I have communicated this to the company [Google] asking them to improve its proposals. We now need to see if Google can address these issues and allay our concerns," the European Commission's competition chief Joaquin Almunia said Tuesday.

If Google?s reply goes in the right direction, Article 9 proceedings will continue. Otherwise, the logical next step is to prepare a Statement of Objections, according to Almunia.

A Statement of Objections is a formal step in the commission's investigations into antitrust business practices, and can lead to prohibition of the specific conduct and a fine of up to 10 percent of the annual worldwide turnover of a company.

The probe into Google started in 2010, following complaints that it favored its own services in search results, with a reduction in the visibility of results for competing sites.