Shares of Harmonic surged 16.5% to $11.87 after the broadband-equipment maker posted a third quarter that blew past Wall Street expectations on virtually every metric—and raised its full-year outlook for the third consecutive time this year. The question now is whether the stock, still down sharply from its 2025 highs, has finally found a floor or is simply riding an upgrade cycle that will eventually cool.

Revenue Crushed the High End of Guidance by $14 Million

Harmonic's Q3 revenue rose 64% year over year to $148.8 million, beating the $131 million analyst estimate , and far exceeding the company's own guidance range of $125–$135 million . Adjusted earnings per share came in at $0.23, topping the $0.17 consensus by 35% . GAAP operating profit jumped to $26.2 million from just $4.0 million a year earlier —a sign that revenue growth is actually dropping to the bottom line, not being spent away.

The "Rest-of-Market" Story Is Becoming the Main Story Harmonic's biggest risk has always been customer concentration: Comcast and Charter together represented 58% of Q1 2026 revenue . That's changing fast. Rest-of-Market revenue—sales to everyone except those two giants—more than doubled year over year and now accounts for a record 46% of total revenue , up from 37% just one quarter ago. Rest-of-Market bookings exceeded 60% of total Q3 bookings , meaning diversification should keep accelerating.

Three Straight Guidance Raises Signal Demand Isn't Slowing

Harmonic raised its 2026 revenue outlook to $545–$555 million , up from $505–$525 million after Q2 and $475–$495 million after Q1. Q4 revenue is guided at $141–$151 million . Full-year non-GAAP EPS guidance now stands at $0.80–$0.84 , well above the $0.67–$0.75 range set in August, suggesting profitability is scaling alongside revenue.

A Leaner Company, but Execution Must Continue

Harmonic completed the $145 million cash sale of its legacy video business to MediaKind in June , leaving it as a pure-play broadband company with a single reportable segment . That focus sharpens the investment case but also eliminates any fallback. Roughly $1.5 million in leftover costs from the video unit lingered in Q3 , a nuisance that should fade. With the upgrade cycle driven by next-generation cable technology and federal broadband subsidies still early, the runway looks long—but the stock's surge already prices in considerable optimism.