Security expert Bruce Schneier has written to blogger and Mercury News technology columnist Dan Gillmor about a patent that seems to be missing from the online US database ('Dangerous' Patent Removed from Database?). He quotes Schneier:

In October 1962, the U.S. Patent Office granted patent 3,060,165 regarding the use of ricin as a biological weapon. Published patents are, of course, publicly available. That's the point.

All US patents are available from the USPTO website: "full-text since 1976, full-page images since 1790." However, for some reason, this particular patent is no longer in the database:

Clicking on "Images" only produces a "Patent not found" image.

The patent is still available in foreign databases, so it seems like a rather futile exercise if the removal was due to concerns about knowledge of WMDs.

This hiding of public information is just the sort of thing we need to fight against. If the bad guys can get a copy of the patent without any trouble, how is this helping?

You can read the three-page patent here: Ricin Patent [PDF].

I wonder if the missing patent has anything to do with a sensationalistic investigative report from NY television station WABC in February of last year that chided the Patent Office for making the patent available (Investigators: Anyone Can Get The Recipe For A Bio-Terror Weapon More Deadly Than Cyanide):

The day before the Secretary of State warned the world about the threat of terrorist ricin attack, I was undercover at the nation's US Patent Office. There, a simple word search on its public computer yielded meticulously detailed instructions on how to make the purest, deadliest form of the poison.

Yeah, like terrorists are going to go to the US Patent Office to do research on biological weapons.

The concern is so great that Ricin will get into the wrong hands the FBI has issued an alert to all law enforcement agencies. Yet just a few miles from the bureau headquarters in the nation's capitol, the US Patent Office allows anyone to get a copy of the Ricin recipe for just 25 cents a page.

Ooookaaay. This is a threat vector we should be worried about because? Anyway, all this sensationalism leads to bogus calls for "increased security."

New York's senior senator says in the interest of national security, the US Army patent needs to be removed from the public domain immediately.

Senator Charles Schumer, New York (D): "For the FBI to be putting out an alert against Ricin and then for the Commerce Department to have this on their computer so anybody can walk in and figure out how to make it, makes the average citizen scratch their head and think, 'What the heck is going on down there in Washington?'

Rest assured Senator, the lack of the patent in the US database means that terrorists will never be able to figure out how to make ricin because even web-savvy bloggers can't get the information very easily .... ooops. Never mind.