The U.N. says the number of international patent filings dropped last year for the first time since 1978 as companies — affected by the global economic downturn — sought fewer new protections on their intellectual property.

The World Intellectual Property Organization, or WIPO, says it received about 155,900 international patent filings in 2009.

This is 4.5 percent fewer than the nearly 164,000 filings it received the previous year.

The Geneva-based WIPO said on Monday that inventors in the United States still registered the highest number of international patents, despite a 11 percent drop.

Third-ranked Germany saw its patent filings drop by a similar amount.

Japan (2nd), South Korea (4th) and China (5th) all increased the number of patents filed at WIPO.

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