[QUOTE=DrageMester;2061738]If you have physical access to the packaging, you can tell that they are Verbatims made by Taiyo Yuden if it says “Made in Japan”.
If you have access to the DVD-R, you can use any number of programs that tells you the media code (e.g. Nero CD-DVD Speed), and if it says TYG03 then it is made by Taiyo Yuden (or YUDEN000 T03 for DVD+R media).[/QUOTE]
i will focus on phisical packaging