Kinderstart sued Google, saying so:
Kinderstart alleges the following facts. Kinderstart operates a website, www.kinderstart.com, which is a directory and search engine for links to information and resources on subjects related to young children. At one point, Kinderstart was “one of the choicest Internet destinations for thousands of parents, caregivers, educators, nonprofit and advocacy representatives, and federal, state and local organizations and officials in the United States and worldwide to access vital information about infants and toddlers.” It launched in May 2000 and at its peak was “presenting in excess of 10,000 page views to visitors on a monthly basis.” ...
On March 19, 2005, Kinderstart’s website “suffered a cataclysmic fall of 70% or more in its monthly page views and traffic.” Kinderstart eventually “realized that common key word searches on Defendant Google’s search engine no longer listed KSC.com as a result with any of its past visibility.” With this drop in search engine referrals, Kinderstart’s “monthly AdSense revenue suffered an equally precipitous fall by over 80%.” Kinderstart concludes that its website “was officially, practically and illegally Blocked by Defendant Google.” Its website has been assigned a PageRank of “0” by the Google Toolbar....
The district court has mostly rejected Kinderstart's claims, including state and federal Free Speech Clause claims, antitrust claims, and state unfair business practices claims, but suggested that a libel claim might prevail, if the complaint is properly amended:
As the parties’ arguments suggest, whether Kinderstart can maintain a claim for defamation may turn on facts outside the pleadings. Google’s statement as to whether a particular website is “worth your time” necessarily reflects its subjective judgment as to what factors make a website important. Viewed in this way, a PageRank reflects Google’s opinion. However, it is possible a PageRank reasonably could be interpreted as a factual statement insofar as it purports to tell a user “how Google’s algorithms assess the importance of the page you’re viewing.” This interpretation would be bolstered by evidence supporting Google’s alleged representations that PageRank is “objective,” and that a reasonable person thus might understand Google’s display of a ‘0’ PageRank for Kinderstart.com to be a statement that ‘0’ is the (unmodified) output of Google’s algorithm. If it could be shown, as Kinderstart alleges, that Google is changing that output by manual intervention, then such a statement might be provably false.
However, Kinderstart’s complaint as presently framed does not explain how it is a false statement about the output of Google’s algorithm regarding Kinderstart.com, as distinguished from an unfavorable opinion about Kinderstart.com’s importance, that has caused injury to Kinderstart. Rather, Kinderstart makes only the conclusory assertion that Google’s actions have “cause[d] irreparable harm and damage to the goodwill, value and revenue-generating capabilities of Kinderstart KSC’s Website ....” Accordingly, this claim will be dismissed with leave granted to amend.
I can imagine two obvious resulting in the pagerank going to 0:
1) Google's algorithm determined that kinderstart was engaged in "ballot stuffing"
2) a person determined that kinderstart was engaged in "ballot stuffing"
The judge makes a distinction between those two that is pretty illusory. Especially if, e.g., repeated applications of 2 were used to train a neural network that led to 1.
(And despite what the complaint said, apparently kinderstart was just a search engine optimization [SEO] site; it had no real content)
Does this really constitute a guarantee that a site's PageRank will always be untouched by human hands? The next paragraph goes on
There's nothing here that looks like a guarantee that a site's import is judged simply by the structure of the net.
The link to the district court opinion is broken. But if Google's explanation is similar to the evidence that was before the court, the opinion's reasoning relies on a generous (to kinderstart) reading of Google's marketing literature.
This raises the question whether the plaintiff is more interested in learning about Google's proprietary technology through discovery rather than in obtaining damages.
I think Google reserves the right to "downgrade" any ranking that they feel is inflated.
I'm not sure if the downgrade was "supposedly without good reason" as opposed to for very good reason, but for reasons KinderStart doesn't want to disclose (as they likely would be decried as spammers) and Google doesn't want to disclose (because they carefully control the release of information which may aid spammers). KinderStart doesn't say "Google didn't have a good reason"; instead they say that the reason wasn't described in Google's webmaster guidelines and thus shouldn't have been held against them. Or at least, that's how I read the complaint.