Piper Jaffray analyst Troy Jensen downgraded iRobot (IRBT) to Neutral with an unchanged price target of $90. The Roomba creator closed Friday up 92c to $106.06.

The analyst continues to believe the robotic vacuum market is in a secular uptrend and that iRobot will "maintain its dominant position in the market."

However, Jensen has become "incrementally more concerned" with the stock's valuation following the year-to-date outperformance. Further, he believes the implemented trade tariffs could impact iRobot's guidance for 2019. Any share rally from the upcoming Q3 results should be used as a selling opportunity prior to the company providing guidance for 2019 in late January, Jensen tells investors in a research note.