Harmonix released multiple Rock Band games during the previous console generation. While all the games were separate many of them gave you the ability to export some or all of the tracks into other Rock Band games. Songs from the first two Rock Band titles along with the family friends Lego version of the title and even the Green Day game could all have songs exported to Rock Band 3 allowing you to have all your music in one place. Harmonix has now revealed details on how you’ll be able to get all that music off the disc and into Rock Band 4, eventually.
Via a post on the Harmonix Blog the developer described their hope that Rock Band 3 songs will be exportable as part of a planned December 8th update. While much of the previous Rock Band DLC is available and is free for anybody who already bought it the first time around, the on-disc music works differently. As with previous songs exports, a key will need to be purchased, which will cost $14.99. Harmonix will be digitally verifying purchase which means you will need to have both bought, and played, the game for the export to work.
Time is actually limited as it appears Harmonix music rights on some or all of the RB3 music is ending and the game will be pulled from digital storefronts October 30th. Any physical copies that are still in the wild will still be valid, but no new copies will be shipped.
It’s also important to be aware that only disc songs that have already been exported to Rock Band 3 will be exportable into RB4. While some old export keys like the ones for the first two Rock Band games have expired, and thus those songs can no longer be added, others like some of the Rock Band Track Packs are still valid. These additional tracks from earlier games will not all be available when the Rock Band 3 export is released, but Harmonix says they will continue to work on it so that players will get access to these songs in the future. Check out the chart below for a full list of what is exportable or not.
Spanish 
English 
French 
German 
Turkish