12 March 2004. The patent was first provided by JP.

A. writes:

According to Dan Gillmore, Bruce Schneier reports that a patent for the production of ricin has been removed from the US patent database, though it is available in foreign databases:

http://weblog.siliconvalley.com/column/dangillmor/archives/010095.shtml

Just in case it disappears from foreign databases, I've attached a PDF of the patent.