It's been accused of that many times informally. At times, it has faced copyright lawsuits over services like its Books search engine, Google News site and YouTube video sharing site.
But on Tuesday, Google's role was reversed. It irately charged Microsoft with sneakily capturing the top Google results for various queries and grafting them into the Bing search engine. It lobbed its complaint in an article on the Search Engine Land blog and continued it during an onstage panel at a search event.
While the merits of Google's accusation are up for debate -- Microsoft denies the charge -- the fact that Google chose to complain in such a loud and agitated manner has become fertile ground for analysis and comment by industry observers.
Opinions range from those who view Google's actions as hypocritical to others who say the company did the right thing by airing its grievance.
Between the two extremes is plenty of speculation. For example, some wonder if the incident reflects a new, more reactive attitude toward slights emanating from Larry Page, the Google co-founder who will become CEO in April and is considered more volatile and less diplomatic than outgoing CEO Eric Schmidt.
"Google's complaint is the height of hypocrisy. The company's entire business model is built on the use of other people's content usually without bothering to seek permission," said John Simpson, from Consumer Watchdog's Inside Google research team.
Google's allegations are an attempt to make Microsoft look bad for doing what every search provider does constantly: analyze competitors' search engines, he said.
"Google's effort to 'trap' Microsoft was a stupid waste of energy that would have been better spent figuring out ways to give consumers true options to protect their online privacy," Simpson said via e-mail.
In a blog post, Roughly Drafted Magazine publisher Daniel Eran Dilger sounded a similar note. "Google copies every original idea it can find, like a massive information sponge, sucking up business models and innovative creations and forming its own duplicates, often with little success," he wrote.
"Google is the world's largest information thief, steamrolling partners, content creators and competitors alike under its concept of the wheels of progress, justifying its dealings as being a free remix and expression of ideas. That's all fine and good if you don't complain about other people also taking the information you publicly offer without a license and then remixing it themselves," he added.
Others have a harder time establishing a direct parallel between the times Google has been accused of copying and Tuesday's incident.
"Although there are parallels, I think this situation is a bit different. In past instances -- YouTube, book search, news headlines -- Google was not copying from a competitor in order to beat that competitor," said Gartner analyst Ray Valdes via e-mail.
Eric Goldman, an associate law professor at Santa Clara University, said it's noteworthy that Google apparently has no plans to sue Microsoft over this. Google likely realizes that in business, it's fair game for companies to copy competitors, as long as what's being copied isn't legally protected under copyright, trademark, patent or other laws, he said.
However, according to Goldman, Google may have set the stage for end-user lawsuits against Microsoft alleging privacy violations. Google said it believes Microsoft is capturing Google user queries inappropriately via Internet Explorer and the Bing toolbar. Microsoft also denies this charge, saying users allow it to capture this "clickthrough" data.
Ultimately, Goldman sees the spat as the latest in a long string of public opinion battles between the two companies. "They look for every opportunity to tweak each other," he said in a phone interview.
Whether coincidental or not, the controversy erupted on the same day of a Microsoft-sponsored search event via an exclusive article on the Search Engine Land blog, which got briefed by Google on its allegations. Google search software engineer Matt Cutts brought up the issue during a panel in which he participated in the event, triggering a verbal scuffle with fellow panelist and Microsoft Vice President Harry Shum.
Some point out that even in the search arena specifically, Google has been itself accused of copying features from competitors, including Bing and Ask.com.
"Google has certainly borrowed from others. I wouldn't say it has stolen outright but it has heavily borrowed at times," said industry analyst Greg Sterling, from Sterling Market Intelligence, in a phone interview.
In this it is not alone, especially among search engines, where "there's widespread watching of competitors and of duplicating things that are seen to be best practices and desirable features," Sterling said.
In addition, in instances such as defending its wholesale digitizing and indexing of library books without always asking for the permission of copyright owners, Google has also relied heavily on the fair use principle, which allows for the unauthorized use of copyright material under certain circumstances and limitations.
"Google has benefitted from a liberal interpretation of fair use," Sterling said. "There is definitely some irony here in Google pointing out that someone else is copying them."
Google didn't respond to a request for comment for this story.
IDC analyst Hadley Reynolds is one of those who questions if the incident is a sign of a new Google attitude in the marketplace with Page at the helm.
"I wonder if this came directly from Larry Page, and thus signals a kind of taking off the gloves and setting up what will be a more aggressively competitive stance [regarding] Microsoft/Yahoo and other tech competitors in the future," Reynolds said via e-mail.
