Shares of Viavi Solutions surged 7.0% to $39.50 on August 17, extending a rally that has now added over 22% in a single week, as investors continued digesting a fiscal fourth-quarter earnings report that beat Wall Street expectations on every major line. In a mixed broader market, the move is almost entirely company-specific — and it raises a pointed question: how much of this growth is repeatable versus acquisition-fueled?
The Numbers Crushed Estimates, and It Wasn't Close
Viavi posted adjusted earnings of $0.34 per share on revenue of $443.1 million, compared with analyst forecasts of $0.30 and $432.62 million.
Revenue came in above its own guidance range of $427–$437 million and grew 52.5% year over year.
GAAP operating margin rose by 850 basis points as operating income climbed to $61.3 million — meaning the company isn't just growing revenue, it's keeping more of each dollar.
A $410 Million Acquisition Is Doing the Heavy Lifting
Revenue rose 52.5% from a year earlier, helped by the Spirent acquisition and strong demand in data-center testing.
The Spirent deal was expected to add roughly $180 million in annual revenue to Viavi's network-testing segment. Strip that out, and organic growth, while solid, is far less dramatic. The legacy service-provider business — field instruments and wireless products — is growing at only 1–2% , a reminder that the old Viavi without acquisitions would look much slower.
AI Data Centers Are the Real Story Behind the Hype
Network-testing revenue in fiscal Q4 grew roughly 70% year over year, primarily driven by continued strong demand from the data-center ecosystem and aerospace-and-defense customers.
Viavi's inclusion in NVIDIA's AI reference architecture gives third-party validation that its tools matter in real AI data-center buildouts. In plain terms, every time a hyperscaler builds an AI server cluster, someone needs to test whether the high-speed connections work — that's Viavi's business.
Guidance Suggests the Momentum Isn't Fading Yet
Management expects Q1 fiscal 2027 revenue between $450 million and $460 million , with a non-GAAP operating margin target of roughly 27.1%.
However, the shift to faster 1.6-terabit networking technology partially replaces demand for existing 800-gigabit products, which could temper overall growth.
Full-year fiscal 2026 revenue hit $1.5 billion despite a net loss of $30.4 million on a GAAP basis , underscoring that acquisition-related costs still weigh on the bottom line. Investors are betting the AI infrastructure wave outpaces those headwinds — the next few quarters will test that conviction.