Jabil Inc. (NYSE: JBL) had a pretty good quarter. The market, apparently, wanted a great one.

Shares fell nearly 7% Wednesday as investors digested the company's fourth-quarter and fiscal 2026 results alongside a new outlook. Trading activity was elevated, with about 2.26 million Jabil shares changing hands, more than double the stock's 100-day average volume of 1.11 million shares.

Here's the thing: the numbers were strong. Jabil reported fourth-quarter revenue of about $10.62 billion, up 29% from a year earlier and comfortably ahead of the $9.69 billion analyst consensus. Core diluted earnings rose 34% to $4.40 per share, beating the $4.06 estimate.

GAAP operating income rose to $602 million, or 5.7% of revenue, up from 4.1% a year earlier. Core operating income totaled $675 million, while core operating margin ticked up to 6.4% from 6.3%.

Intelligent Infrastructure Is Doing the Heavy Lifting

The star of the show was Intelligent Infrastructure, where revenue jumped 56% to about $5.8 billion. That was roughly $900 million above Jabil's June outlook, which is not a small beat.

The company credited stronger artificial intelligence demand, an earlier-than-planned capacity ramp, a second hyperscaler program in Mexico and networking strength in India. The segment's core operating margin rose 60 basis points to 6.5%, helped by a better business mix and the Hanley Energy acquisition.

Elsewhere, Regulated Industries revenue increased 9% to $3.4 billion, with a 5.8% core operating margin. Automotive and Transportation and Renewable and Energy Infrastructure both performed better than management expected. Connected Living and Digital Commerce revenue was roughly flat at $1.4 billion, with a 7.1% margin.

For the full fiscal year 2026, Jabil's revenue increased 21% to about $36 billion. Core operating margin expanded 40 basis points to 5.8%, while adjusted free cash flow exceeded $1.5 billion.

The Fiscal 2027 Outlook Is Where It Gets Interesting

Jabil expects fiscal 2027 revenue of about $44.5 billion, up 24% and above the $42.64 billion analyst estimate. The company forecast core earnings of $17.55 per share, also above the $16.80 estimate, with adjusted free cash flow expected to reach about $1.6 billion.

For the first quarter, Jabil expects revenue of $10.6 billion to $11.4 billion, compared with the $9.942 billion analyst estimate. Core earnings are expected to range from $3.80 to $4.20 per share, above the $3.60 estimate.

Management Says This Isn't Your Father's Contract Manufacturer

CEO Mike Dastoor said Jabil has shifted toward higher-value engineering and supply-chain work. Gross margin has increased by more than 200 basis points since fiscal 2020 to 9.2%. Core return on invested capital has nearly tripled to 59%, while net capital spending has declined to 1.3% of revenue.

"We are not a contract manufacturer competing with low-cost EMS companies. Nor are we a product company competing with our customers," Dastoor said. "We build a diverse set of capabilities and deploy them in whatever combination the customer needs to deliver complex solutions for their products and services."

Management said demand for AI infrastructure "remains strong and continues to accelerate." Jabil ended fiscal 2026 with four customers generating more than $1 billion each in annual AI-related revenue, and management expects that customer base to broaden.

The company is expanding its data-center capabilities through Hanley Energy, which adds power engineering, deployment and services. Earlier investments in high-speed interconnects, optics and technology acquired from Intel support emerging co-packaged optics and networking programs.

Jabil also highlighted its alliance with Adani Group around India's data-center buildout. Its acquisitions of Mikros Technologies and Hanley Energy have expanded its liquid-cooling and power capabilities.

Beyond AI infrastructure, management sees opportunities in defense and aerospace, healthcare, energy infrastructure, warehouse automation and physical AI. Jabil expects to manufacture more than 700 million injectors and delivery pens in fiscal 2027, and cited its work with Symbotic as an example of its ability to scale complex automation products.

Dastoor said data-center demand continues to exceed supply, adding that capacity investments planned for fiscal 2027 could also support further growth in fiscal 2028.

But About That Memory Problem

Here's where the story gets a little less comfortable. Jabil warned that memory availability is becoming a growing supply-chain constraint as capacity shifts toward AI and hyperscale customers. Management said it is seeing "real constraints" in memory, with supply tightening across several of Jabil's end markets.

"We're seeing real constraints today. Memory, in particular, is being reallocated towards AI and hyperscale demand, tightening supply across many of the diversified end markets that we serve," management said, adding that Jabil views the pressure as "a structural shift in global capacity compounded by ongoing geopolitical disruption."

That's the kind of sentence that makes investors nervous, even when the headline numbers look great. When memory gets scarce, costs go up, timelines slip, and margins can get squeezed. And when a company says the constraint is "structural," it's signaling this isn't a one-quarter blip.

JBL Price Action: Jabil shares were down 6.81% at $297.13 at the time of publication on Wednesday.