This opposition by CBS softened after Sony, a DAT manufacturer, bought CBS Records in January 1988. By June 1989, an agreement was reached, and the only concession the RIAA would receive was a more practical recommendation from manufacturers to Congress that legislation be enacted to require that recorders have a Serial Copy Management System to prevent digital copying for more than a single generation.[5] This requirement was enacted as part of the Audio Home Recording Act of 1992, which also imposed taxes on DAT recorders and blank media. However, the computer industry successfully lobbied to have personal computers exempted from that act, setting the stage for massive consumer copying of copyrighted material on materials like recordable CDs and by extension, filesharing systems such as Napster.[6]