IBM’s (NYSE:IBM) patent portfolio is like one of those massive vault doors one sees in banks – incredibly heavy and imposing, and apparently impenetrable. What’s more, that portfolio continues to grow more imposing by the year.

In 2011, IBM won 6,180 patents from the U.S. Patent and Trademark Office, up from 5,896 patents in 2010 and enough to make it the top patent winner for the nineteenth straight year, according to an analysis by IFI Claims Patent Services, a patent data specialist. Asian companies, meanwhile, gained serious ground in the patent realm, noted a Bloomberg post on the IFI analysis: Samsung Electronics (PINK:SSNLF), whose patent acquisitions outpaced IBM’s, placed second; Canon (NYSE:CAJ) replaced Microsoft (NASDAQ:MSFT) in third; Panasonic (NYSE:PC) moved up to No. 4; and Toshiba advanced to fifth.

However rapidly other companies may advance their patent acquisitions, though, IBM’s portfolio will remain one of the technology world’s most powerful assets, and a huge obstacle for competitors who try to challenge it.

“Everyone knows that if they attempt to bring their patent portfolio against us that they will be met with an equal and opposite force — and it will be formidable,” IBM’s chief patent counsel, Manny Schecter, told Bloomberg.