After news broke that the Texas Attorney General’s office is just the latest to open an antitrust investigation into Google’s business practices, a company attorney wrote a blog post that indirectly pointed a finger at Microsoft.

Three days later, the Wall Street Journal reported that Microsoft and spin-off Expedia are among the companies U.S. Justice Department officials have contacted during its antitrust probe into Google’s planned acquisition of ITA Software. Microsoft also was vocal during hearings for Google’s book-scanning settlement, and its Italian subsidiary Ciao Bing filed an antitrust complaint in Europe against Google’s search practices.

No stranger to antitrust investigations, Microsoft essentially is Google’s last remaining competitor in search. But is Microsoft, as Google Deputy General Counsel Don Harrison seems to suggest, pulling the strings in Texas?

In his blog post, Harrison highlights three companies that have been contacted by the Texas A.G.’s office. Little-known search engines Foundem, TradeComet and MyTriggers all have ties to Microsoft, Harrison wrote.

Foundem, which filed an antitrust complaint alongside Ciao Bing to the European Union’s Competition Commission, is “backed by ICOMP, an organization funded largely by Microsoft,” Harrison claims. In fact, it was with the help of ICOMP (the Initiative for a Competitive Online Marketplace), which has lobbying ties to Microsoft, that Foundem was able to turn its grievances into a formal complaint, the Financial Times reported.

Harrison went on to tie TradeComet and MyTriggers to Microsoft because they use the same antitrust law firm as the Redmond-based company. This also is true: Cadwalader, Wickersham and Taft — based in Washington, D.C. — and its figurehead partner Charles “Rick” Rule famously represented Microsoft in the late 1990s in United States v. Microsoft.

Cadwalader, however, is one of just a few large law firms that specialize in high-tech antitrust issues. Chances are, if you’re an Internet company, your antitrust attorneys have done business with Microsoft.

But The Wall Street Journal reported earlier this year that Microsoft referred TradeComet to Cadwalader. MyTriggers noticed, called TradeComet and was referred to the same firm. Additionally, Microsoft representatives have told seattlepi.com numerous times that companies often call Redmond to get referrals to antitrust laywers, and that Microsoft usually helps out.

Yet all three companies contacted by the Texas A.G. have asserted their independence from Microsoft. Like Foundem, TradeComet and MyTriggers each have filed their own antitrust claims against Google in other courts.

“MyTriggers’ case is its own,” a spokesperson told seattlepi.com. “There may be a lot of companies who have suffered harm, but our case is focused on the harm to MyTriggers resulting from Google’s anticompetitive conduct and bullying tactics.

“We have a strong antitrust claim and look forward to our day in court. Our attorneys at Cadwalader, along with the Ohio firms representing us, are excellent lawyers and are not intimidated by Google’s sharp-elbowed tactics.”

Dan Savage, CEO of TradeComment, sent seattlepi.com a decidedly less-wordy statement: “Obviously, Google is just trying to distract from its own antitrust problems by pointing to others and their lawyers.”

Foundem, based in the United Kingdom, did not immediately return a seattlepi.com request for comment. But its chief executive, Shivaun Raff, recently spoke with The Register about the Texas investigation.

“You have an overwhelmingly dominant search engine,” she told The Reg. “If you add to that that search engine’s ability to apply discriminatory penalties — they’re discriminatory because some services are manually rendered immune through white lists — and you add the ability of that search engine to preferentially insert its own services at or near the top of the search results, all of that adds up to an unparalleled and unassailable competitive advantage.”

These days, antitrust investigators are honing in on Google’s core business: search. Unlike past cases, including the Google Books settlement and the company’s AdMob acquisition, the Texas investigation is looking at Google’s search rankings. Foundem, TradeComet and MyTriggers have claimed Google intentionally tweaks its search results to surface its own products and services higher than those of its competitors.

These sites each offer search services in specific verticals, or topics. Foundem bills itself as “the U.K.’s top price comparison site.” TradeComet’s SourceTool.com is a business-to-business directory with listings based on the United Nations Standard Products and Services Code (UNSPSC). MyTriggers is a comparison-shopping engine that aggregates listings from eBay, Amazon and other sites.

There are other similar antitrust claims against Google, as well. In some cases, Google offers competing services in these verticals. In others, companies allege Google unfairly surfaces their websites further down in its search results.

Google, for its part, says its search results are tailored for Web users, not for Internet companies, and are powered by its successful algorithms. It has argued as much in court, and has pointed out that competitors obviously have their own agendas in filing antitrust complaints.

And the big competitor, of course, is Microsoft.

“It appears that our large competitors are injecting themselves into complaints by smaller firms against Google, likely in order to learn more about our business practices and use that information to develop a broader antitrust complaint against us,” Google spokesman Adam Kovacevich told seattlepi.com.

Microsoft denied to comment specifically on the Texas investigation, though a source said the company has not received any formal requests for information from the attorney general’s office. (No formal request is needed — investigators can call up companies for information without sending official requests.)

A spokesperson pointed to a February blog post by Microsoft’s Dave Heiner, vice president and deputy general counsel, which explains Microsoft’s role in a number of antitrust probes into Google.

“Complaints in competition law cases usually come from competitors,” Heiner wrote. “This is the way that competition law agencies function: They look to competitors in the first instance to understand how particular markets operate, the practices of dominant firms and the competitive significance of those practices.”

Interestingly, Google’s Kovacevich pointed to the same blog post as proof that Microsoft is attempting to wage an antitrust war against Google.

Then there’s this May article (PDF) from The American Lawyer magazine titled “The Google-Slayers,” which examines Cadwalader partner Rule’s “crusade” against the alleged Google monopoly. It was published before the Texas investigation at least became public.

“Rule denies that Microsoft is directing things behind the scenes, and says that Microsoft isn’t paying the firm’s bills,” wrote reporter Seth Hettena. “But if Cadwalader is working for anything like its normal rates, its fees threaten to far exceed the amounts that either MyTriggers or TradeComet ever owed Google.”

(MyTriggers filed an antitrust counterclaim after Google sued it for delinquent payments.)

“Rule says that some of the companies Cadwalader represents may make their voice heard in Europe, but he remains vague about his broader assault on Google,” The American Laywer reported. “Several other businesses have contacted Cadwalader with grievances about Google, he says. How many? ‘More than a handful,’ is all he will say.”

Indeed, the big question now is whether Foundem, TradeComet and MyTriggers were, as Google’s blog post suggests, the only three companies the Texas Attorney General’s office contacted.

An A.G. spokesman would only confirm the investigation for seattlepi.com and declined to go into any detail. Cadwalader partner Jonathan Kanter said he didn’t know if other companies had been contacted. Kovacevich would only say the three are “among” the companies Texas contacted, and declined to discuss the case further.

Considering the mounting opposition to Google — and considering the U.S. Justice Department contacted Microsoft, Expedia, Orbitz, Kayak and others regarding the planned ITA Software acquisition — odds are Foundem, TradeComet and MyTriggers were not the only companies Texas contacted.

They were three examples Google’s Harrison chose to highlight, likely because of their connections to Microsoft and its attorneys. But were they singled out? Are Harrison’s claims founded?

Is Microsoft the puppetmaster in Texas?

Google says yes; Microsoft says no. If Microsoft and Google are engaged in a war of Titans, Foundem, TradeComet and MyTriggers seem to be caught up in a war of spin.