What happened

Shares of iRobot Corporation (NASDAQ:IRBT) dropped 10.2% on Tuesday following a short-seller's renewed attack on the home robotics specialist.

So what

More specifically, short-selling firm Spruce Point Capital announced it has reestablished its short position in iRobot, marking an update to a scathing report it issued on iRobot stock three years ago while suggesting it could face "20% to 50% downside risk." To justify its bearishness, Spruce Point argues that iRobot's recent outperformance "reflects restocking of its supply chain after years of false starts, the removal of the struggling military business, and the acquisition boost from its Japanese distributor," all of which could create tough year-over-year comparisons going forward.

Spruce Point also drew attention to "disruptive competition" coming to the U.S. market, where iRobot holds 88% market share in the robotic vacuum space, as well as its move to "finally" file an ITC patent infringement complaint against multiple well-known competitors only after "years of promoting the value of its intellectual property."

iRobot Roomba 960

IMAGE SOURCE: IROBOT CORPORATION.

Now what

As a longtime shareholder of iRobot myself, I strive to keep an open mind regarding its downside risk. And similar to its last report in 2014, the points above are only a few of Spruce Point's criticisms of iRobot. But also similar to last time -- when I called out Spruce Point for two glaring incorrect assumptions underlying its bearish thesis, not to mention its oddly sensationalist tone -- I have similar doubts following a cursory look at its latest work. 

Regarding the patents, for example, it ignores that iRobot has successfully enforced its IP portfolio multiple times over the past decade. And it was no mystery that iRobot's Defense & Security business had struggled given unpredictable government budgets, which is exactly why the company divested it to hone its focus on the lucrative home robotics space.

While they do lament that iRobot still depends much on its flagship Roomba vacuum line, there's also no mention of iRobot's promising Braava line of floor mopping robots. Most notably, Braava comprised 25% and 40% of total revenue in Japan and China, respectively, last quarter, up from 10% and 25% in the same year-ago period -- a testament to iRobot's astute move to take advantage of predominantly hardwood floors in Asian households.

To be fair, shares of iRobot are still up more than 150% over the past year as of this writing, so it's not entirely surprising investors might take a step back given Spruce Point's latest piece. However, as a long-term investor, I'm not particularly concerned for iRobot's ability to survive and thrive.

Steve Symington owns shares of iRobot. The Motley Fool owns shares of and recommends iRobot. The Motley Fool has a disclosure policy.