Google sure has its work cut out for itself in terms of regulatory defense these days. The latest is that the company’s offices in South Korea have been raided by that country’s version of the FTC – The Korean Fair Trade Commission.

According to Jay Greene at CNET, who first reported on the raids, regulators are looking int o Google’s alleged limiting of access to rival search engines on its Android platform.

Google’s statement on the matter:

“We will work with the KFTC to address any questions they may have about our business. Android is an open platform, and carrier and OEM partners are free to decide which applications and services to include on their Android phones. We do not require carriers or manufacturers to include Google Search or Google applications on Android-powered devices.”

Web search and Android are also at least parts of the reason the company is being probed by the FTC here in the U.S.

Google has a hearing with the U.S. Senate Antitrust subcommittee scheduled for September 21.

The company also faces regulatory scrutiny over its proposed acquisitions of AdMeld and Motorola Mobility.

When the FTC investigation was announced, Google laid out five principles that it says will hold up to scrutiny, which the company is likely relying on for any such regulatory scrutiny:

• Do what’s best for the user. We make hundreds of changes to our algorithms every year to improve your search experience. Not every website can come out at the top of the page, or even appear on the first page of our search results.

• Provide the most relevant answers as quickly as possible. Today, when you type “weather in Chicago” or “how many feet in a mile” into our search box, you get the answers directly—often before you hit “enter”. And we’re always trying to figure out new ways to answer even more complicated questions just as clearly and quickly. Advertisements offer useful information, too, which is why we also work hard to ensure that our ads are relevant to you.

• Label advertisements clearly. Google always distinguishes advertisements from our organic search results. As we experiment with new ad formats and new types of content, we will continue to be transparent about what is an ad and what isn’t.

• Be transparent. We share more information about how our rankings work than any other search engine, through our Webmaster Central site, blog, diagnostic tools,support forum, and YouTube. We also give advertisers detailed information about thead auction and tips to improve their ad quality scores. We’ve recently introduced even more transparency tools, announcing a major change to our algorithm, providing morenotice when a website is demoted due to spam violations, and giving advertisers new information about ads that break our rules.

• Loyalty, not lock-in. We firmly believe you control your data, so we have a team of engineers whose only goal is to help you take your information with you. We want you to stay with us because we’re innovating and making our products better—not because you’re locked in.