Here’s an interesting change about to occur: when Mozilla pushes the launch button for the next version of the Firefox browser (version 14), the default search engine in Russia will no longer be local Internet services giant Yandex but global market leader Google.

The Yandex search service, which was added as the default option in Russian-language Firefox builds starting early 2009, has a market share in Russia of approximately 60 percent (Google has about 26,5 percent).

ff In Russia, Yandex will be replaced by Google as default search option in new Firefox

The commercial agreement between Mozilla and Yandex is notably set to expire on the 31st of December 2012, which begs the question: why was Yandex ousted in favor of Google in the most recent Russian-language Firefox browser build way before that date?

For the record, Mozilla wasn’t contractually bound to keep Yandex as the default search option in the Russian Firefox build – but still, why the change?

A Yandex spokesperson says they were notified by Mozilla of the imminent change on June 1, and points out that the company will continue to develop and distribute its own Yandex-branded, customised Firefox browser (at least until the end of this year, under the terms of the aforementioned agreement).

The latter version evidently sports Yandex as the default search engine.

yandexf In Russia, Yandex will be replaced by Google as default search option in new Firefox

Yandex also says Mozilla’s decision will likely not impact its market share in Russia significantly (they estimate a 1.5 percent loss over the next few months).

From a Yandex spokesperson:

Default search in a browser is not the only or the key factor that defines a share in the search market. As before, we will keep making our services better, improving their functionality, design, efficiency and comprehensiveness – as it is our firm belief that no matter what service the browser is equipped with, it will be used only if it satisfies users’ demands.

Yandex’s search share in Google Chrome that has more complicated settings for changing the default search than Firefox, is bigger that Google’s, which is the default search engine in this browser.

A default search engine, however, does matter for beginner internet users or for those who still are not sure what search engine they prefer. That is why we will keep offering to visitors on our websites an option to choose Yandex as a default search engine in their browser – this is an easy way to use Yandex without typing the address for those who have been using it anyway.

Yandex adds that the impact on its revenue and profitability will be negligible.

From what we can gather, Google has been putting pressure on Mozilla to become the default search option in Firefox in Russia as part of a global, 3-year agreement struck between the companies (which is said to be a $900 million deal).

The Mountain View, California-based search giant has always been keen on being the default search engine in browsers, partly because a lot of people increasingly search the Web straight from the address bar.

We’ve reached out to Google and Mozilla and are awaiting clarification from them.