U.S. stocks lost ground on Friday, with the tech sector snapping a three-day winning streak with a flourish.

The tech-heavy Nasdaq fell 1.9% on Friday after results from Snap (SNAP) weighed on the sector and sent shockwaves through the digital ad market.

The benchmark S&P 500 dropped 0.9% and the Dow lost 0.4% during the week's final trading session.

All three major indexes, however, finished the week with modest gains.

The fallout from Snap's (SNAP) disastrous fourth quarter earnings report weighed on tech stocks to finish the week, with shares of the social media company losing 39% on Friday.

Snap reported revenue that was slightly light of estimates, but the company's commentary on the overall ad market and its decision not to offer formal guidance spooked investors. The company also said third quarter revenue growth was tracking to flat over the prior year.

In its quarterly letter to shareholders, Snap said, in part: "Platform policy changes have upended more than a decade of advertising industry standards, and macroeconomic challenges have disrupted many of the industry segments that have been most critical to the growing demand for our advertising solutions. We are also seeing increasing competition for advertising dollars that are now growing more slowly."

"Increasing competition" is seen by most observers as a sign that TikTok continues to pressure its peers in the social media space.

Shares of Meta Platforms (META) were also down over 7% on Friday in sympathy with Snap's decline. Meta will report is own second quarter results next Wednesday after the market close.

Data from Bloomberg showed Snap's decline took at least $76 billion of market value off digital ad-related stocks, with shares of Alphabet (GOOG) and Pinterest (PINS) also falling on this news.

Elsewhere on the earnings calendar, shares of Verizon (VZ) lost more than 6% on Friday after the company reported second quarter earnings that disappointed.

Results from American Express (AXP) out Friday morning were received positively by investors, with CEO Stephen Squeri telling Yahoo Finance he sees no signs of recession when looking at his business. The company raised its full-year revenue outlook, and shares gained 2% during a down day for the markets.

AmEx did increase provisions for credit losses in Q2 by $410 million, a move we saw big banks make last week as some consumers hunker down amid rising inflation.

Twitter (TWTR) also reported earnings that missed expectations on Friday, with revenue grow missing expectations and the company reporting a loss against expectations for a modest per-share profit.