SAN FRANCISCO — The headlines swirling around Alphabet, the parent company of Google, are not positive: European regulators are cracking down on its business practices, politicians are expressing concern about political bias, and there are growing fears about how it is pushing the boundaries on user privacy.

But those clouds have done little to darken Alphabet’s earnings — a testament to the enduring strength of Google’s core search business. In 2018, Google is expected to capture about 60 percent of global search advertising spending, according to the research firm eMarketer.

On Thursday, Alphabet reported a net profit of $9.19 billion in the third quarter, up 37 percent from a year earlier. Quarterly revenue was $33.74 billion, an increase of 21 percent but slightly lower than analysts expected, pushing the company’s stock price down about 5 percent in after-hours trading.

Alphabet’s profits, however, exceeded analysts’ estimates, reflecting a lower tax rate that it attributed to the impact of tax cuts passed in the United States last year. Alphabet’s quarterly tax rate was 9 percent versus 16 percent a year earlier.