Harmonic's Broadband Roars Back 43% in Q1, Guides Higher; Video Sale on Track

What happened

Harmonic reported Q1 2026 broadband revenue surged 43% year-over-year, with Rest-of-Market jumping 78%, and raised its full-year broadband outlook to $475-495 million, signaling a robust DOCSIS 4.0 ramp. The Video business sale to MediaKind remains on schedule to close in Q2, consistent with prior guidance. This strong quarterly performance marks a sharp reversal from the 38% broadband decline in Q3 2025, but the base period was weak and the recovery is in early stages. Management's raised guidance implies confidence in sustained growth, though execution risk remains given extreme customer concentration (Comcast ~40%) and the pending sale's completion. Overall, the quarter provides the first tangible evidence that the broadband recovery thesis is taking hold, but skepticism is warranted until revenue growth broadens and backlog stabilizes above $500M.

Implication

Harmonic’s Q1 results provide the first clear evidence that the DOCSIS 4.0 cycle is gaining momentum, supporting a potential upgrade from WAIT to a modest BUY, but only after confirming that the Video sale closes cleanly and that broadband growth persists in Q2. The raised full-year guide ($475-495M) implies broadband revenue acceleration through 2026, validating the earlier thesis that the 2025 downturn was a temporary pause. However, extreme customer concentration and the fact that Q1 easy comps helped the 43% growth mean investors should wait for Q2 results to confirm the trend before increasing position size. A disciplined entry near $10 or below offers a better risk/reward versus chasing the stock after a 40% rally from October lows.

Thesis delta

The Q1 results shift the thesis from cautious wait-and-see to cautiously constructive: broadband recovery is materializing ahead of prior expectations, with 43% YoY growth and raised guidance supporting a higher probability for the base case ($11) and a path to the bull case ($13.50). However, the rally likely already discounts much of this good news, and the risk of a later-stage ramp or share loss (as flagged in the master report) remains elevated given Comcast's outsized influence. The key new watchpoint is whether backlog and deferred revenue stabilize or decline further, as the Q1 reported revenue increase may reflect pull-forward rather than sustainable demand.