Amazon said on Thursday that it will begin offering music from Sony BMG without digital rights management, allowing purchases to freely distribute the downloads.
The deal makes the online retailer the first company to offer songs in the Mp3 format from all major music companies, Amazon said.
Sony joins the ranks of its rivals to offer songs that will work across various players, including Apple's iPod and Microsoft's Zune.
EMI, the number four music company in market share, became the first major company to drop DRM in April. It was soon followed by Vivendi's Universal Music Group, which ranks No. 1, and Warner Music Group.