Satellite radio companies XM Satellite Radio Holdings, Inc. (NASDAQ: XMSR) and Sirius Satellite Radio Inc. (NASDAQ: SIRI) have continued normal operations as they await the approval on their proposed merger. The stocks, however, declined some 30% since the merger announcement. Although many knew the regulatory approval of the only two satellite radio companies would not be easy, faith in the approval seems to be going lower every day, affecting the share prices of both companies in recent months.

Isn't a merger agreement supposed to hike share price instead of sinking it? Generally, this happens, however, when it involves telecommunications and a threat of possible market monopolization, then the reverse happens. Although, when I liveblogged Sirius's latest quarterly results, CEO Mel Karmazin sounded supremely confident that the merger process would be approved after just a few more roadblocks. Potentially myopic investors don't agree, apparently.

I don't think that this merger is violates antitrust regulation. While it appears that way from the single-minded antitrust regulators, consumers today have more choice on in-car entertainment now than ever before. FM stagnation getting you down? Use that "auxiliary input jack" on most new vehicles and listen to anything from your MP3 collection. Older car? No worries, use and FM transmitter. Still like terrestrial radio? Get HD Radio for those FM broadcasts with CD quality. Antitrust concerns here? Unless you can only use satellite radio (for some odd reason), it's highly doubtful.