International patent filings increased by 6.6 percent in 2012 from the previous year, with China, Japan and South Korea posting double-digit growth, the World Intellectual Property Organisation (WIPO) said Tuesday. \"This is once again telling a story of quite robust growth in the system, despite the weak international economic climate,\" Francis Gurry, head of the UN agency, told reporters. \"It shows the importance of building strong, intangible asset portfolios, even in times of crisis, because you need it for a recovery,\" he said. \"While demand may have been relatively flat in Europe, it has been quite robust in Northeast Asia,\" he added. WIPO oversees the Patent Cooperation Treaty (PCT), which allows patent-seekers to file a single application to protect their invention, rather than having to lodge one in individual nations. A total of 194,400 PCT applications were filed last year, with the United States accounting for 51,207, up 4.4 percent on 2011. Japan-based inventors made 43,660 filings, representing a 12.3 percent increase. China, meanwhile, was a whisker behind third-ranked Germany, the source of an unchanged 18,855 filings. \"China was within 250 of taking over Germany,\" noted Gurry, saying there had been expectations that it would leapfrog the European economic powerhouse. Chinese PCT filings rose by 13.6 percent in 2012, the figures showed. South Korea completed the top five, with its 11,848 filings representing a 13.4 percent increase. Gurry underlined the \"remarkable\" continued growth in Northeast Asia -- China, Japan and South Korea -- and the region\'s share of the global PCT filings. Back in 2008, the three countries accounted for a little more than 26 percent of applications, he said. By 2012, the share topped 38 percent. \"As that has increased, Germany and the US for example, over the same period went from 43 percent to 36 percent,\" Gurry stressed. Chinese telecommunications group ZTE was the largest individual patent filer last year, with 3,906 applications, ahead of the Japanese conglomerates Panasonic and Sharp and China\'s Huawei. Despite Europe\'s economic gloom, there were stand-out performances by the Netherlands, posting a 14-percent increase in PCT filings, and Finland, up 13.2 percent. WIPO also runs the Madrid system for international trademark applications, which grew by 4.1 percent in 2012. \"That generally is a pretty good indicator of economic activity starting to pick up, because trademarks are usually new products, services or enterprises,\" said Gurry. Their geography is distinct from that of patents, he noted, with Japan, Britain and the US accounting for 80 percent of growth, and Swiss pharmaceuticals giant Novartis the biggest single applicant.