Stock analysts with some of the nation's top investment firms are altering their ratings of XM Satellite Radio and Sirius Satellite Radio stock on speculation that the two companies may merge.

According to Forbes, analysts at JP Morgan and Bank of America made adjustments Tuesday - one upward, and one downward.

Although there was no confirmation of a merger as of press time on Jan. 16, XM's management publicly endorsed a possible merger last week.

Top officials at Sirius have been talking about a merger for months.