ClickZ: Exposed Sender ID Patents Up Debate

The U.S. Patent office revealed last week Microsoft's patent applications regarding Sender ID, throwing the anti-spam standard's efforts to gain wide adoption into significant doubt. Microsoft had been cagey about just what claims it was making to the standard, attempting to get industry standards bodies to endorse it prior to understanding what the software giant was claiming as proprietary intellectual property. Microsoft fended off doubts about adopting a proprietary standard by promising to make the licensing free, although it would also require signing a Microsoft license agreement, which can sometimes involve wide-ranging terms.

The claims, as revealed in the patent applications cover a wide swathe. ClickZ interviewed John Leveine, chairman of the Anti-Spam Research Group, and found his interpretation of the claims to be "if you look up the sending domain's policy and you do something with it" that it is covered by the patents, "and that's really broad."

The patents applications are 20040181571 and 20040181585 and can be found on the Patent Office's site.