CMC Magnetics and Ritek, two of the world's biggest producers of optical media, along with smaller companies Prodisc Technology and Lead Data, recently received a slap in the face from Philips. Due to various violations of licensing contracts, Philips has revoked the patent for CD-R media for these companies. The reasons were varied, but the end result is the same. Shipments of CD-Rs from these companies to other countries may be impacted by this:

Prodisc confirmed it received notification of license revocation from Philips late last month. Since the revocation of patent licenses is expected to prevent exports of CD-R discs to Europe and the US, CMC, Ritek, Prodisc and Lead Data all indicated they will soon meet to discuss how to handle the situation.
This only affects CD-R based discs, and doesn't have any impact on DVD media. Other companies still have valid patents through Philips, and the specific reasoning behind all the revoking isn't made clear. Because of the popularity of CD-R media, these companies won't waste any time in getting back in each others good graces.