Although a number of companies have attempted to put together a large database of barcodes, none have exceeded 30 million barcodes - at least as far as we know, up till now. Alibaba.com - soon to be the world's largest shopping portal - claims to have a database of 100 million barcodes, as reported by Want China Times.
Recently, according to Want, Alibaba held a promotion to encourage users to scan barcodes on mobile devices by offering a discount to users who did so. Their campaign reportedly attracted over 1 million buyers.
The largest databases we are aware of elsewhere include- www.ShopSavvy.com - reported 20+ million barcodes about 2 years ago.