In a declaration filed with US financial regulators, Online retail giant Amazon has revealed that 11 companies have filed patent lawsuits against it since the start of 2011. This is more than 3 times the number from all of the previous year, BBC News is reporting.

Amazon vows to dispute the 30 pending claims and intends to “vigorously defend” itself. Complaints include charges that Amazon infringes intellectual properties owned by other businesses, and that its Kindle ebook devices use technologies owned by two others.

MasterObjects, a Dutch developer specializing in search result software has had one suit thrown out that claimed Amazon’s drop-down search suggestions infringed one of its US patents.

Virginia-based LVL Patent Group claims Amazon’s mobile applications and other technologies breach four of its innovations. The litigator also launched claims in September against Apple, Siemens, Hewlett-Packard and Nokia, among others.

Andrea Matwyshyn, assistant professor of legal studies at the University of Pennsylvania’s Wharton School told BBC about the crop of lawsuits, “It is quite common in the technology industry to have aggressive patent litigation. In fact, the volume against Amazon pales compared to other industries such as the mobile phone sector, which is involved in a series of patent wars.”

However, Amazon’s legal troubles may mount following the launch of its first tablet computer.

“These lawsuits can only continue to increase, especially as Amazon makes more hardware,” Colin Gillis, senior technology analyst at BGC Partners, told BBC. “The field is clogged with lawsuits, particularly with products that run on Google’s Android software, which its new Kindle Fire tablet uses.”

Amazon’s filing suggests it was sued by three claimants over a total of four patents in 2010. Amazon settled one of the cases and still disputes the others.

(Source: RedOrbit Staff & Wire Reports)