LEADING THE DAY: Microsoft will file a complaint with the European Commission as part of its antitrust investigation into Google. In a Wednesday night blog post , Microsoft’s general counsel, Brad Smith, said Google is impeding competition in Europe by “walling off access to content and data.” Smith cites several examples of Google actions that have concerned Microsoft. Those include the assertions that Google restricts competing engines’ YouTube searches and that Google denied Windows a fully functional YouTube player for the Windows Phone, as well as several concerns about how Google interacts with ads and advertisers.

Smith acknowledged that there is a “certain irony” in Microsoft’s filing an antitrust complaint, noting that this is the first time the company such a complaint. “Having spent more than a decade wearing the shoe on the other foot with the European Commission, the filing of a formal antitrust complaint is not something we take lightly,” he wrote.

Amazon negotiating Cloud music rights: Bloomberg and The Wall Street Journal cite sources Thursday morning that say Amazon is negotiating with record labels to obtain licensing for its much-touted Amazon Cloud Player streaming music service. Amazon has said that it doesn’t require the licenses to stream users’ music, contending the service is no different than storing music on a hard drive. However, licensing the music would make the system more efficient — the company would be able to stream the same file to multiple users if it obtained the licenses — and Amazon is said to be aggressively pursuing agreements with music companies.

Acer CEO resigns: Acer chief executive Gianfranco Lanci has resigned, the company announced in a press release issued this morning. The resignation is effective immediately. Acer Chairman J.T. Wang will step in as acting CEO.

In the release, Acer said Lanci “held different views from a majority of the board members, and could not reach a consensus” following several months of discussion on the future of the company. The board and the chief executive disagreed on matters of “scale, growth, customer value creation, brand position enhancement, and on resource allocation and methods of implementation,” the company said.

Patent overhaul in the House: The House Judiciary Committee subcommittee on Intellectual Property, Competition and the Internet held a hearing on patent system changes Wednesday. Rep. Lamar Smith (R-Tx.), the House Judiciary chairman, filed a patent overhaul bill that is very similar to the one passed in the Senate earlier this month. Both propose a switch to a first-to-file system as well as provisions that would allow the U.S. Patent and Trademark Office to keep its own fees.

In the hearing, the main objections raised were over a post-grant review process that would allow third-party companies — including international companies — to challenge patents.

Google launches social search feature: Google had a big day on Wednesday, making two major announcements and settling with the FTC over privacy concerns with its Google Buzz network. In addition to announcing the winner of its Google Fiber contest, the company launched a new social search feature, +1. The new experimental feature, currently an opt-in experiment only, allows users to endorse links through Google searches. The endorsements, or +1’s, are then coupled with the links in other user searches.