The federal case about the nighttime hum at Microsoft’s Fairwater campus in Mount Pleasant, Wisconsin, is not moving. On September 23, U.S. District Judge J.P. Stadtmueller signed a text-only order that stopped the lawsuit because the people who filed it and the company they sued told him they have a preliminary settlement. Nobody has published the terms. The next date on the docket is not a trial. It is November 2, 2026, when the parties must either ask the court to approve the deal or file a status report explaining why they cannot.
The case is Ostergaard v. Microsoft Corporation, No. 2:26-cv-01169, in the Eastern District of Wisconsin. Garret Ostergaard, David Wade, and Joy Wade filed it on July 1, a class-action complaint with a jury demand. They live in Sturtevant, close enough to the building at 4800 90th Street that they say the sound reaches their bedrooms. They sued for themselves and for a class their lawyers put at about 1,000 homes within roughly a mile and a half. The legal labels are private nuisance and negligence. The human label, in the complaint, is that a house stopped working as a place to sleep.
What the neighbors say the building does at night
The complaint says Fairwater throws off unreasonable noise from diesel backup generators and from the cooling plant: chillers, cooling towers, air handlers, and condenser fans. It says the noise is not a spike. It is constant. It also draws a distinction that ordinary noise ordinances often miss. Some of the equipment is loud on a standard decibel meter. Much of what residents describe as a low hum is low-frequency sound that a dBA reading is built to under-count. A village can publish a number that says the plant is legal and a household can still feel the sound in a wall.
Ostergaard’s account, as pleaded, is specific. He had been working a third shift. He moved to a second shift because the noise was wrecking his sleep. The Wades say they cannot use their deck the way they used to. The complaint quotes a neighbor, Beth Kane, describing the sound as a nightmare that brought headaches, and describing box fans left running so the house had some other noise to hide it. Those are allegations in a pleading, sworn in the way a complaint is sworn, and they had not been tested by a trial when the parties asked the judge to stop the clock.
Their lawyers, Laura Sheets of Liddle Sheets in Detroit and Michael Lueder of Hansen Reynolds in Milwaukee, said in a July 2 release that this suit sits in a run of similar cases the Detroit firm has filed against data centers. Wisconsin Public Radio and the Milwaukee Journal Sentinel both covered the filing the day after it hit the court. The pattern those stories describe is no longer exotic. Facilities in other states have drawn noise suits and violation notices of their own. Fairwater is the Wisconsin version, and it arrived the same summer the building went live.
Microsoft’s own timeline does not match a shrug
Microsoft has not treated the hum as imaginary. On a public local blog, the company posted a series of notes from the Mount Pleasant site it calls Fairwater 1. The April 15 entry says neighbors north of the campus noticed a tonal hum as equipment came online. Engineers traced it to cooling fans running at high speed. Microsoft said it had expected some startup noise and had not expected the tone to travel as far as it did. The company said it was adjusting the fans by hand and hoped the tonal problem would be addressed by April 20.
The June 18 entry goes further. Microsoft said tests and mitigations were in place, that independent monitoring lined up with what several neighbors reported, and that those mitigations had fully resolved the issue for the people who confirmed it. The same note says short-term work was continuing and that more sound-reduction hardware would be installed over the following months. A July 20 note says engineers and consultants were still evaluating sound at the facility. Read in order, the posts admit a tone, claim a fix, and then keep measuring. They are not a court judgment. They are the company’s account of a problem it says it found.
The campus itself is the first of a series of buildings Microsoft has planned for the site, and the company has promoted it as an AI training hall. Public descriptions now line up on the scale local television has used: a campus of about 315 acres and a building on the order of 1.2 million square feet, drawing enough power that counsel for the neighbors say Microsoft has talked about a future need on the order of 900 megawatts. Reporting on the opening has put the Wisconsin investment at $7.3 billion. Satya Nadella had already told the public, in April, that the site was ahead of the original schedule. By June, Microsoft was calling the hall operational. The lawsuit landed on July 1.
How a noise case reaches a stay instead of a motion to dismiss
Microsoft’s lawyers, including Paul Benson and, later, a Faegre Drinker team with Matthew Olsen, Henry Kelln, Kirstin Stoll-DeBell, and Elizabeth Scheibel, did not file the dismissal motion the calendar had made room for. In August the court restricted an executive summary the parties wanted kept off the public record. On August 14, Stadtmueller let the plaintiffs file a second amended complaint by August 31. They did, and they kept the jury demand. On September 8 the court said Microsoft could move to dismiss by September 29. That motion does not appear on the docket.
What appears instead is ECF No. 21, filed September 22 at 3:46 p.m.: a joint motion to stay, and a notice that the two sides had a preliminary settlement. The next afternoon, at 4:30 p.m. on September 23, Stadtmueller granted it. Proceedings are stayed. By November 2 the parties must move for preliminary approval or tell the court, together, where things stand. The public docket, checked after that order, shows nothing newer. A preliminary settlement is a plan to settle, not a check, not a construction change, and not a class member’s release. Until a judge approves it, the class does not exist as a bound group, and the neighbors who were never asked are not stuck with a deal they have not seen.
A hum is a land-use fact, not a branding problem
Data-center fights in 2026 are usually about water, tax abatements, or the electric bill. Fairwater’s federal case is about sound that people say they cannot sleep through. That is a smaller headline and a harder engineering problem. Low-frequency noise does not photograph. A decibel chart can be waved at a council to prove compliance while a third-shift worker changes jobs. Microsoft’s June note says some neighbors signed off on the fix. The complaint says other households did not. Both can be true on a campus this large, which is why a class definition of „about a thousand homes“ was always going to be the fight if the case had stayed on a litigation track.
The November 2 filing will tell the public which track won. If the motion for preliminary approval arrives, it should say what Microsoft will build, what it will pay, and who is in the class. If a status report arrives instead, the stay was a pause, not a peace. Either document will be more informative than a blog post that says the tone has been handled. The AEGIS Alliance has been tracking the other side of the same buildout, including the scramble for AI computing power and the way a single social-media line about a chipmaker can move a stock. Fairwater is the version of that story with a street address and a deck nobody wants to sit on.
Until November, the legal status is simple. The case is open, the claims are unresolved, and a federal judge has agreed to wait. Readers following technology news and U.S. news at The AEGIS Alliance should treat every claim that the hum is „solved“ as somebody’s press line. The docket says the parties think they can settle. It does not yet say the night is quiet.
