What happened

Shares of Criteo (NASDAQ:CRTO) were down 15.9% as of 2:45 p.m. EDT Wednesday after the ad-retargeting technology specialist announced mixed third-quarter 2019 results, named a new CEO, and issued disappointing forward guidance.

So what

More specifically on the former, Criteo's revenue excluding traffic acquisition costs (ex-TAC) declined 1% year over year (but was flat at constant currencies) to $221 million, technically near the high end of constant-currency guidance provided in late July. That translated to adjusted net income of $35.5 million, or $0.54 per share. Though we don't usually pay close attention to Wall Street's quarterly demands, most analysts were modeling lower adjusted earnings of $0.49 per share on slightly higher revenue of $221.8 million.

Stock market chart on a colorful display indicating losses.

IMAGE SOURCE: GETTY IMAGES.

"We have reached key milestones in our transformative journey," added Criteo founder and CEO JB Rudelle. "With a clear direction and augmented leadership, I am confident Criteo will succeed as the leading tech platform for the open Internet."

As for Criteo's executive turnover, the company also announced it has appointed Megan Clarken as CEO effective Nov. 25, 2019. Clarken most recently served as chief commercial officer of Nielsen Global Media. Rudelle will remain as chairman of the company's board of directors.

Now what

Looking ahead to the fourth quarter, however, Criteo sees revenue ex-TAC arriving between $255 million and $261 million, good for a constant-currency decline of 5% to 3%. As such, Criteo now expects its full-year 2019 revenue ex-TAC to be roughly flat at constant currency, or near the low end of its previous outlook.

With shares having rebounded around 25% from their 52-week low set in June -- albeit still trading down sharply from their March highs -- it's no surprise to see Criteo stock falling in response today.