"Be it known that I, EZRA CORNELL, of Ithaca, in the county of Tompkins and state of New York, have invented a new and useful Machine or Implement for Laying Metallic Pipes in the Earth, which I denominate 'Cornell's Improved Pipe-Layer;' and I do hereby declare that the following is a full and exact description of the construction and operation of the same, reference being had to the annexed drawings ..."

So begins U.S. patent No. 3456, dated Feb. 28, 1844, covering the pipe-laying device that helped to make Cornell University founder Ezra Cornell's fortune.

Patents haven't really changed much since then. The process of obtaining a patent is still long and complex, fraught with legal pitfalls and requiring constant attention. For Cornell-affiliated inventors, that attention is provided by the Cornell Center for Technology, Enterprise and Commercialization (CCTEC). In 2005 CCTEC filed 203 applications for U.S. patents and 55 patents overseas. The university holds 614 U.S. and 264 overseas patents through Cornell Research Foundation (CRF), a university subsidiary administered by CCTEC.

Patents can cover physical objects, from pipe-laying machines to new drugs, or processes, such as a new procedure for synthesizing an old drug or a computer algorithm to run a factory. On the other hand, a mental process, scientific principle or business practice can't be patented.

CCTEC handles other categories of intellectual property besides patents, including certificates of plant variety protection obtained through the U.S. Department of Agriculture, which confer rights to new plant varieties, like Clancy and L'Amour raspberries and several varieties of wine grapes and apple rootstock. And CCTEC administers what is known as "proprietary biological material." "We own lots of licenses to antibodies, cell lines and plant-breeding markers -- little bits of DNA that mark the location of genes," explains Richard Cahoon, interim executive director of CCTEC.

A patent is a piece of intellectual property. Like any other property, it can be bought, sold or, in effect, "rented." The owner of a patent often licenses to someone else the right to manufacture or use the invention, usually in return for a royalty. Royalties paid to CRF by licensees of Cornell intellectual property are generally divided one-third to the inventor, one-third to Cornell (60 percent to the inventor's unit and 40 percent to the university) and one-third to CRF to cover administrative and patent expenses. In 2005 CRF distributed $3.5 million in net revenues.

To begin the process, the inventor files an invention disclosure with CCTEC. Along with a brief description of the invention, CCTEC also needs to know if the inventor's research was sponsored by or done in collaboration with other academic institutions, an outside company or government agency that could have some rights in the invention.

Previous publication in a scientific journal might make it impossible to obtain a patent. "We often walk a fine line between the commercial possibilities of an invention and the researcher's need to publish," Cahoon says, "and we will always defer to the researcher." However, in the United States a patent application can be filed within one year after publication, he adds.

The invention gets a preliminary screening by one of CCTEC's technology managers for obvious flaws. If the idea seems to be worth pursuing, the next step is a "prior art" search -- scanning the Patent Office and the literature for similar ideas. This has been made a lot easier by computers, but it still requires special skills. It involves examining the "claims" of existing patents. These are often carefully worded by patent attorneys to be as broad as possible. If you have invented a laser bread slicer, for example, you would probably find that someone else claims to own the idea of a device for slicing bread, and that claim is broad enough to cover any type of cutting device. You might, however, be able to claim the idea of a device that slices bread and toasts it at the same time.

Assuming the idea is patentable, the next step is a market analysis. A few years ago a Cornell researcher came up with the idea of a coin-operated garbage can for highway rest areas. While the idea was patentable, it was obvious that few would ever put a quarter in such a machine. Wendell Roelofs, the Liberty Hyde Bailey Professor of Insect Biochemistry at the Agricultural Experiment Station in Geneva, N.Y., and his colleagues purified a sex pheromone for the Italian cockroach, but it turned out there are no Italian cockroaches in North America. "Patentable but not marketable," Cahoon says. Roelofs and his collaborators also extracted and purified a sex pheromone from the German cockroach, the most common variety found in the United States, and Cornell now receives significant income from licensing the pheromone to the manufacturers of cockroach bait.

Outside attorneys with various technical specialties prepare Cornell patent applications. Approval by the U.S. Patent Office can take from two to four years, as Cornell's attorneys and examiners in the Patent Office negotiate over the precise wording of claims. The entire process can cost from $18,000 to $25,000 or more. Meanwhile, if the invention warrants, separate applications must be submitted for patents in foreign countries, one country at a time.

After all this, U.S. patent protection lasts just 20 years from the date of filing the application, after which the idea passes into public domain. This is part of the underlying purpose of the patent (and copyright) system, derived from Article 5 of the U.S. Constitution: that innovation should be encouraged by granting inventors the right to profit from their inventions "for a limited time," but that eventually new ideas should be made widely available.

As if Cornell people really need encouragement to come up with new stuff.