Google is facing fresh accusations of anti-competitive behaviour, following reports that the US Justice Department is investigating the internet giant over its dealings with the book industry.
Lawyers for the government are examining potential antitrust issues surrounding a $125m settlement made between Google and authors - in a move that could scupper the internet company's plans to create an "iTunes for books".
The deal, struck last autumn between the web giant and authors' groups, would see Google pay $125m for the right to digitise millions of books in the US, with the intention of selling the files online and taking a significant cut of the profit.
The proposed settlement came after two years of negotiations and legal wranglings, and was hailed at the time as a "great leap" by Google co-founder Sergey Brin.
But the proposals have concerned some other campaigners, particularly because it would give Google exclusive rights to digitise so-called orphan works - books that are still under copyright, but without any clear owner.
Peter Brantley of the Internet Archive, a San Francisco-based organisation that documents millions of web pages and digitises out-of-copyright books, said that there had been ongoing conversations between concerned parties and the Department of Justice.
"There are legitimate antitrust issues related to Google's ability to solely commercialise this content," he told Reuters.
As a result of similar, worries a judge in New York yesterday granted a four-month extension to allow those affected by the deal to examine the details and decide whether to opt out of it or not.
That move pleased campaigners, who said they are worried that it could damage the industry to hand too much power over to one company.
"We now have time to really sink our teeth into what this agreement will mean," said Gail Knight Steinbeck, chair of the Creative Property Rights Alliance and daughter-in-law of late author John Steinbeck.
At the moment, the deal would only affect authors in the United States, but Google has previously said that it is in discussions with other organisations around the world about similar proposals.
It is not the first time that Google has raised the attention of government lawyers thanks to its increasing dominance in the online world.
Last year it emerged that the Department of Justice had started an investigation to explore whether a proposed link between Google and Yahoo could have an unfair impact on the internet advertising market.
High profile litigator Sandy Litvack was brought in to run the operation, which was eventually curtailed when Google announced that it was backing out of the deal.
Subsequently the pressure appeared to be relieved thanks to the relationship between the White House and Google's chief executive, Eric Schmidt, who acted as an adviser to the Obama campaign. That bond was reinforced earlier this week when Dr Schmidt was named as one of the first members of a Presidential advisory committee on science and technology.
However, not everybody inside the administration has such warm feelings towards the Californian internet powerhouse. Christine Varney - Obama's nominee to run the Department of Justice's antitrust division - has already voiced concerns about Google's power, saying she could "see a problem, potentially, with Google".
Varney, who was part of the team who fought a long-running antitrust case against Microsoft in the 1990s, told a meeting in Washington last year that "Microsoft is so last century", but that Google could pose a threat because it "has acquired a monopoly in internet online advertising".
