It's no news flash that the economy has been struggling for over a year, with the high-tech sector taking the biggest beating. But you'd never know it by looking at patent activity. The U.S. Patent and Trademark Office received a record flood of 344,717 patent applications in 2001, as companies worldwide beefed up their patent portfolios. The intellectual-property principle for the post-dot-com world: patent or perish.

So, too, reads the message that jumps off the pages of Technology Review's latest Patent Scorecard. Based on data from CHI Research of Haddon Heights, NJ, the scorecard annually tracks the U.S. patenting activity of 150 top companies in eight key high-tech sectors. The project goes beyond mere patent numbers to rank the quality and strength of each company's portfolio according to its comparative relevance.

Once again, the editors have delved deeper into U.S. patenting activity by identifying a handful of patents issued last year that are of special note. Be they stem cells that can help repair or replace any tissue in the human body, systems that speed up wireless communications or novel materials and software algorithms used to build, store and process information, these "Five Patents to Watch" (p. 73) represent advances that could transform a number of industries-or even create new ones.

But it's the scorecard that tells the broader story, setting the stage on which these individual dramas will play out. Its figures show that from autos to pharmaceuticals to computing and all manner of electronics, patent activity is booming. The biggest surges last year came in information technology and telecommunications. Semiconductor companies saw an average increase of 21.4 percent in the number of patents issued from 2000 to 2001. Similarly, patenting grew 20.4 percent in the telecom industry, and in computing 11.6 percent. Even more impressive, U.S. Patent and Trademark Office statistics suggest the penchant for patents among information technology companies will continue; these three sectors saw the highest numbers of new patent applications filed in 2000, the latest year for which data are available.