Yahoo has lost a battle to keep information about its operations confidential after a judge decided to unseal documents filed by shareholders suing the company over its handling of Microsoft's unsolicited acquisition offer.

Delaware Chancery Court Judge William Chandler ruled on Monday that the court shouldn't keep documents such as the plaintiff's complaint under seal, despite Yahoo's arguments to the contrary.

Now, the complaint and the judge's decision have become available on the Web on the site of Bernstein Litowitz Berger & Grossmann LLP, a law firm representing the plaintiffs.

The 64-page complaint is chock-full of blistering allegations, copies of internal Yahoo documents and e-mails and blow-by-blow accounts of what plaintiffs characterize as Yahoo bad-faith maneuvers. It will likely have a damaging public opinion effect on Yahoo, as the company battles other lawsuits and gets ready to face a proxy fight led by Carl Icahn to replace its board members in July. The complaint had been made available previously but with portions redacted.

"We're disappointed with the ruling in Delaware, but this is a routine legal matter and we're sure it won't have any impact on the outcome of the case, which we believe is without merit," said Yahoo spokeswoman Diana Wong.

The class-action lawsuit, filed in February on behalf of Detroit's Police & Fire Retirement System and General Retirement System, alleges that Yahoo's directors and top managers failed to look out for shareholders' best interests by rejecting Microsoft's offer.

The plaintiffs allege that directors and top managers, including co-founder and CEO Jerry Yang, actively tried to derail Microsoft's efforts to negotiate a mutually beneficial acquisition agreement. The complaint places much of the blame on Yang, describing him as someone with a "well-known" antipathy toward Microsoft who acted out of a personal interest to keep Yahoo independent.

Meanwhile, the plaintiffs blame the directors for allegedly relying on Yang to lead the negotiations with Microsoft, but Yang instead "used that power to delay, to refuse to negotiate in good faith and to erect roadblocks," the complaint reads.

In particular, the plaintiffs take issue with Yahoo's change over employee severance plans, which the plaintiffs interpret as a way to scare Microsoft away from the deal, "throwing sand in the gears of Microsoft's plans for a smooth integration."

The IDG News Service is a Network World affiliate.