Rav Avraham Yosef, Chief Rabbi of Holon, dealth with an interesting, and always controversial topic in his halacha radio program today. The issue of making copies of discs. The variety of opinions regarding this issue is as wide as the variety of possible opinions.

Rav Yosef said that regarding discs of Torah shiurim, even though the rabbi worked hard to put out his shiur on a disc and spent money, one is allowed to copy the disc. Rav Yosef said that nobody owns the Torah, and therefore no matter how much work one puts into it, anybody can make copies of this type of Torah content. Rav Yosef adds that this remains the halacha even if the rav specifically speaks out that he forbids making copies - it remains allowed.

Rav Yosef differentiates between Torah and music. Where it is allowed to copy discs of Torah, it is prohibited to copy discs of music. The artist has ownership of his work, and copying discs, it does not matter how many, is theft. (source: Kikar)