Shares of iRobot (NASDAQ: IRBT) fell 14.2% on Thursday as investors speculated over the implications of an upcoming meeting of the U.S. Federal Trade Commission (FTC) on Amazon's (NASDAQ: AMZN) pending acquisition of the home-robotics specialist. After the regular session closed, however, iRobot stock plummeted another 40% in after-hours trading following a separate report that European regulators are planning to block the deal.

Amazon's bluff seems to have backfired

Recall that iRobot stock also fell last week amid reports that Amazon had opted not to offer concessions to European Union (E.U.) antitrust regulators as it works to clear its impending purchase of the Roomba maker. The move sparked speculation over whether Amazon was content to allow the acquisition to fail or it was instead calling E.U. regulators' bluffs, given prior reports that the deal was previously set to win unconditional approval.

Investors were already on edge this week after a U.S. federal judge blocked a separate pending merger between JetBlue and Spirit Airlines and amid worries that an FTC meeting scheduled for next week on an undisclosed topic might involve the Amazon-iRobot merger.

After the regular market session closed today, however, The Wall Street Journal reported that in a meeting with European Commission (EC) officials earlier today, Amazon representatives were told that the deal would likely be rejected in the absence of concessions to address the E.U.'s antitrust concerns.

What's next for iRobot investors?

It remains to be seen whether Amazon will push forward with the acquisition. The $1.7 billion purchase consideration for the deal is relatively inconsequential to the tech giant, given its $1.59 trillion market capitalization. But bringing iRobot under its wing would also significantly bolster Amazon's smart-home ambitions, particularly given iRobot's enviable trove of smart-home and robotic navigation patents.

iRobot could also continue its path as a stand-alone company -- albeit with some work to do to reramp research & development and sales & marketing expenditures and to clean up its balance sheet after taking on additional debt to fund operations as it awaited the deal's completion.

In the meantime, it's no surprise to see iRobot stock falling on this news.

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