What happened

Microinverter manufacturer Enphase Energy Inc.'s (NASDAQ:ENPH) strong run continued on Monday, when shares climbed 13.1% in afternoon trading. Gains slowed with about two hours left in trading, and at 2:55 p.m. EST, shares had settled to a 9.3% gain for the day.

So what

Investors are still likely processing a great earnings report from early last week, and the news late in the week that CEO Badrinarayanan Kothandaraman had acquired 40,000 shares on the open market.

Home with solar panels on its roof

Image source: Getty Images.

The CEO's purchase was a $132,800 bet that the company's turnaround would continue, despite headwinds like tariffs on solar imports into the U.S. Enphase has filed for an exclusion from imports, but there's no guarantee the company will get one from the Trump administration.

Now what

There wasn't any specific driver of shares today, other than the momentum continued from last week. But it can take a while to adjust expectations and price as sentiment on a company becomes more bullish.

Despite the bullishness of the past week, I will point out that Enphase Energy did lose money in the fourth quarter of 2017, and guidance indicates another loss in the first quarter of 2018. The company's rapid decline may be slowing, but betting on a turnaround in operations is still risky for investors.