An Ottawa software application developer has won a legal battle against a company he describes as a "patent troll."

Larry Dunkelman created a free app called "Bus Buddy" that uses GPS data from the transit company to tell riders when to expect their bus.

In May, Dovden Investments Inc. filed a claim in Federal Court against Dunkelman after first demanding $10,000 in licensing fees. The company said his software infringed on a patent related to vehicle tracking technology invented by a Vancouver man.

"It was like getting mugged, but in slow motion," said Dunkelman of the lawsuit.

Dovden Investments owns a portfolio of patents, but does not produce any software or technology. Companies like it that licence their patents — and defend those patents through litigation — are often referred to derisively in technology circles as patent trolls.

32 lawsuits in Canada in last year

Dunkelman is not the only one to be hit with patent litigation from Dovden.

Beginning in 2006 with a claim against the Vancouver Airport, Dovden has launched 42 lawsuits in Canada, including 32 in the last year.

Dunkelman was the fourth client lawyer Geoff North has defended against Dovden.

Dovden withdrew its suit in August, but North said he wonders if Canada needs to do a better job protecting people like Dunkelman.

"We can't have these broad patents being enforced against individuals like Larry," said North.

"We need to stop this situation from occurring because we need to be able to have people like Larry develop good things for people instead of suing people for doing so," he said.

Urban transit group sues Dovden

In August, the The Canadian Urban Transit Association filed its own suit against Dovden, claiming the company's patents are invalid.

"Dovden's threat is costly litigation," said CUTA president and CEO Michael Roschlau in a statement.

"Most publicly funded transit agencies could not sustain such legal costs in addition to efficiently serving transit users on a daily basis. At the same time, responsible public authorities cannot ignore a patent infringement lawsuit or the opportunity to settle such a suit."

But Bruce Lemer​, the lawyer for Dovden, said the company has a legitimate patent, one approved by the federal governments in both Canada and the U.S. for more than 15 years. Lemer said the company has a right to defend its patent.

Earlier this year, the American Public Transportation Association filed a similar lawsuit against ArrivalStar, a foreign investment corporation with ties to Dovden Investments.

Earlier this week, New Zealand passed a law to prohibit the patenting of computer software.

IT experts and supporters of open source software have long been lobbying for a patents ban, arguing the process of developing software necessarily draws on aspects of existing programs and allowing patents on such material greatly restricts the kind of cross-pollination needed to develop new software.