Between 6/11 and 7/15, if you buy a qualifying song (by OLDCODEX, GRANRODEO, JAM Project, nano.RIPE or Chihara Minori) from recochoku, animelo mix, music.jp, mora, or the Oricon music store, you will be eligible for a variety of prizes, including A) a Lantis Matsuri signed by GRANRODEO, JAM Project or Chihara Minori (1 winner), B) a special postcard from GRANDRODEO, OLDCODEX, JAM Project or nano.RIPE (30 winners).
Each site has its own application procedures, so be sure to check the requirements when you make your purchase. Entrants may not designate if they want A or B. That will be chosen at random.
Details can be found on the Lantis site.