A federal judge has given a company suing Google a chance to amend its complaint before he decides whether to dismiss the case.

Judge Jeremy Fogel of the US District Court for the Northern District of California, in San Jose, granted Google's motion for dismissal pending amendments to KinderStart.com's complaint.

KinderStart, which operates a web portal about caring for young children, sued Google in March. The Norwalk, California, company said Google gave it a "zero" ranking in its PageRank system and blocked KinderStart.com from the Google search index. The suit charged Google with defaming KinderStart, violating its free-speech rights, and using monopoly power for unfair competition. KinderStart's site includes a web search function.

Part of KinderStart's suit claims Google breached a contract under its AdSense program, in which it carries ads distributed by Google and earns commissions when users click on them. KinderStart is also seeking class-action status for the suit, saying many other companies similarly have suffered by getting left out of Google search results.

Judge Fogel ruled on Thursday that KinderStart's arguments were insufficient, but he gave the company a chance to amend each one.

KinderStart's best prospect for keeping the case alive may come with its argument that Google has defamed the company by giving it a PageRank of zero.

Because of the way Google presents its PageRank system, which is the basis of all its web search tools, the public might conclude the rankings are facts that Google arrives at strictly through an algorithm, Judge Fogel wrote. If KinderStart could show that Google manually changes the results of the PageRank system, then Google's presentation of the rankings as objective might be false, he wrote.

Google said at a 30 June hearing that the average user would recognise its page rankings as opinions, not facts.

In May, Google filed two motions to have the case dismissed. One attacked the foundation of KinderStart's arguments and the other invoked California's anti-SLAPP (Strategic Lawsuits Against Public Participation) law, written to prevent suits that are designed to chill public debate. By suing Google, KinderStart is trying to alter the company's speech because it doesn't like what Google has to say, according to the motion.

At the 30 June hearing, Google told Judge Fogel that its website rankings are opinions that are based partly on a mathematical algorithm and partly on Google studying the quality of sites and making subjective judgments. The company can use any criteria it wishes for the rankings and doesn't have to tell anyone how it does them, said David Kramer, a lawyer from Wilson Sonsini Goodrich & Rosati who was representing Google.

At that hearing, Judge Fogel put off consideration of the anti-SLAPP motion until a 29 Sept hearing. At that hearing he will also hear arguments on a motion by KinderStart for a preliminary injunction that would make Google restore the company's site to its index while the case is in court.