The big four ad revenue-producing digital media companies — Google, Facebook, Twitter and Snap — are expected to see a collective steady 25% increase in ad dollars in the third quarter, according to one analyst.

Michael Nathanson, senior research analyst of MoffettNathanson, says this will mimic the same 25% gain in the second quarter of this year. Yet there is some concern.

“We expect increased scrutiny in the U.S. and EU (European Union), which could create an overhang that hinders prospects for further multiple expansion of these companies.”

This caveat comes from heightened concern over Russian-backed advertising actors, fake accounts and other ad issues that have plagued the business for some time. “That said, these issues likely had no impact on fundamentals in the third quarter,” he added.

Nathanson expects 19% ad-revenue growth in the period for Google (up from 16% in the second quarter); 42% for Facebook (down from 47%); 6% lower for Twitter (versus a 8% drop in the second quarter); and 76% more for Snap.

For Google, this means $27.3 billion in third-quarter total gross revenue; for Facebook, $9.8 billion; for Twitter, $510 million; and for Snap, $225 million.