Earlier this week, Google officially announced that it has agreed to acquire ad optimization firm AdMeld, and now, as expected it appears it will draw government scrutiny. Pretty standard really.

Bloomberg is reporting that the $400 million deal will be reviewed by the U.S. Department of Justice, citing two people familiar with the matter. Since all transactions over $63 million have to be reported for review by authorities, and this one in particular involves Google and advertising, this hardly comes as a shock.

The publication shares a statement from Google spokesperson Rob Shilkin, who says that the deal won’t hurt competition, and “The acquisition is designed to help publishers get the most from the rapidly growing display advertising industry, which is both complicated and incredibly competitive — the emergence in recent years of a huge variety of technologies for publishers, like Admeld’s, is great evidence of that.”

Earlier this week, on the Official Google Blog, Neal Mohan VP of Display Advertising wrote:

By combining Admeld’s services, expertise and technology with Google’s offerings, we’re investing in what we hope will be an improved era of flexible ad management tools for major publishers. Together with Admeld, we hope to make display advertising simpler, more efficient and more valuable, provide improved support and services, and enable publishers to make more informed decisions across all their ad space. These are all things our publisher partners have been asking us to further invest in. Of course, Admeld will continue to support other ad networks, demand side platforms, exchanges and ad servers, to yield the best possible results for publishers.

We believe that this investment will be an important step to help online publishers, and will further improve and grow the display advertising industry as a whole.

The investigation will reportedly aim to determine if Google’s dominance in search advertising could make this an anticompetitive buy, and will examine Google’s plans for expansion strategies related to the acquisition. The DoJ has not commented.

Meanwhile, an FTC investigation into Google’s broader search dominance and competitive practices is also expected to take place.

The DoJ recently approved Google’s $700 million acquisition of ITA Software.