A day before the online music video service is scheduled to go live, Vevo locked in its third major label licensing deal with EMI Music.

According to the agreement, EMI will add its catalog of music videos to that of Universal Music Group and Sony Music Entertainment for the ad-supported streaming video service. It also includes videos from independent labels and artists represented by the EMI Label Services and the Caroline Distribution division.

Vevo remains a joint venture between Sony Music Entertainment, Universal Music Group, and investor Abu Dhabi Media. Sources close to the deal say EMI is only licensing its content to the service and is not an equity partner in the company.

The sole holdout at this time is Warner Music Group, but both parties confirm that negotiations are ongoing. Warner recently struck a deal with YouTube that gives the label its own branded channel within the video sharing service designed to drive fans to artists websites. YouTube provides the underlying technology for the Vevo service. A number of independent labels, artists and digital aggregators are on board with Vevo as well.

Vevo is scheduled to go live Dec. 8, highlighted by a launch party in New York that the company described as a sort of "up front" type unveiling similar to what TV networks give for advertisers in advance of their upcoming programming season.