(Reuters) - International Business Machines Corp (IBM.N) was granted the most U.S. patents for the 23rd year in a row in 2015, according to a ranking by patent analysis firm IFI Claims Patents Services.
There were 298,407 utility patents granted in 2015, down slightly from 2014, IFI Claims said on Wednesday. IBM gained 7,355 patents last year. Utility patents cover function rather than design.
Among the technology giants notable for their intellectual property, Alphabet Inc's (GOOGL.O) Google stepped up its patent activity, moving to the fifth position from eighth in 2014, while Apple Inc (AAPL.O) stayed at the 11th position.
Patents are sometimes the subject of legal battles, and investors, analysts and enthusiasts alike track patents closely to see what companies are looking to develop next.
Following IBM, Samsung Electronics Co Ltd <005930.KS> and Canon Inc (7751.T) rounded off the top three spots, the ranking showed.
The U.S. patent counts for 2015 fell for the first time since 2007, according to the ranking.
Microsoft Corp's (MSFT.O) patents dropped significantly in 2015, sliding to tenth on the list with a near 31 percent decrease in patents.
Companies such as Microsoft and Panasonic <6752.T> have assigned some patents to newly formed holding companies, which explains why several entities dropped considerably lower in the rankings, IFI said.
"Rather than keeping all corporate patents under a single registration, some companies are choosing to spread their portfolios across multiple entities," said Larry Cady, an analyst at IFI Claims.
(Reporting by Anya George Tharakan in Bengaluru; Editing by Cynthia Osterman)