50 Cent–real name Curtis Jackson–has today (September 17) blamed Kanye West’s record label Def Jam for yesterday’s chart defeat, saying Def Jam had been “rigging” sales.

The two rivals were battling it out for number one in the charts–with West’s Graduation beating 50 Cent’s Curtis.

West’s single “Stronger” has also beaten 50 Cent’s “Ayo Technology” in the U.K.–charting at #3 and #5, respectively.

Sean Kingston’s “Beautiful Girls” remains at number one in the U.K. singles chart for a third week running.

Curtis Jackson had declared that he would quit making solo albums if he was beaten by his rival in the ongoing feud, prior to the records’ releases last week.

Jackson now insists that West’s label Def Jam must have doctored the sales figures, saying: “He’s never had a fraction of the sales 50 Cent has. They could have one scan and have it count four times. West’s entire career hasn’t sold half what I sold on my first album.”