President Barack Obama held his second public Google+ hangout today, taking questions from Americans from around the country the day after his State of the Union address.

During the event, an issue came up that's pretty important in the tech world, but still marginal or even largely unknown to the nation at large: patent trolls, the shell companies that have no business beyond suing over patents.

Mike Masnick at Techdirt captured a transcript of the exchange. Adafruit founder Limor Fried told Obama that when talking to colleagues, "what I hear is that they're afraid that if they become successful, they're going to be targeted by patent trolls." She went on to ask what the president would do "to limit the abuse of software patents?"

Obama's answer indicated he clearly understood the nature of the problem, although he also nodded towards the complexity of solving it. First, he acknowledged the recently enacted patent bill hasn't solved all the problems in the system, which is true, but an understatement. The president continued:

The folks that you're talking about are a classic example. They don't actually produce anything themselves. They're just trying to essentially leverage and hijack somebody else's idea and see if they can extort some money out of them. Sometimes these things are challenging. Because we also want to make sure that patents are long enough, and that people's intellectual property is protected. We've got to balance that with making sure that they're not so long that innovation is reduced.

Reform efforts had gone "about halfway to where we need to go," he said.

Some other tech issues that might have had even more public resonance didn't come up. Over at Townhall.com, Derek Khanna put together a list of the 10 most popular questions submitted to Obama. The eighth most popular question, with 1,220 votes in favor, was submitted by the group Public Knowledge. It read: "Mr. President, would you support a small, targeted fix to copyright law that allows folks to use the devices and digital media that they have already paid for, however they like, and for their own personal use?"

The president chose not to answer that one. It's an issue that's recently been highlighted, since cell phone unlocking just became illegal again after being legal for six years. Khanna, who spoke briefly to Ars after the Google+ hangout, said only one question on that list actually got answered by Obama.

A petition on that issue has received almost 70,000 signatures on the White House site. The Obama administration has agreed to respond to any petition that gets 100,000 signatures within 30 days, which leaves the cell phone unlocking petition 10 days to reach that goal.