Economic Damages Expert’s Customer-by-Customer Lost Profits Method Upheld
Posted on June 23, 2025 by Expert Witness Profiler
Sonrai specialized in data tools for waste collection companies. Heil, a well-known manufacturer of garbage trucks—referred to in the industry as refuse collection vehicles (RCVs)—entered into a written agreement with Sonrai in July 2014. The purpose was to facilitate the exchange of confidential information and explore a potential partnership, where Sonrai’s data product, “Vector,” could be integrated with Heil’s RCVs.
Over the next year, both companies shared proprietary information and operated under the terms of the agreement. In May 2015, Heil made an offer to acquire Sonrai, but Sonrai declined. The relationship began to deteriorate, and by September 2016, Heil chose a different path. It acquired a company called 3rd Eye, opting to use 3rd Eye’s competing data product, “Enhance,” instead of continuing with Sonrai.
Following this turn of events, Sonrai filed a lawsuit against Heil for breach of contract. Sonrai also accused Anthony Romano of breaching his fiduciary duties to Sonrai. Sonrai also alleged that Anthony Romano had breached his fiduciary duties owed to the company. Heil, in turn, countersued, also alleging a breach of contract.
Defendants raised certain arguments about the reliability of Sonrai’s damages expert Suzanne Stuckwisch‘s testimony.
Economic Damages Expert Witness
Suzanne M. Stuckwisch has more than 30 years of experience in economic and financial analysis and engineering consulting. She holds a B.S. in Mechanical Engineering, an M.B.A., and an M.S. in Economics.
Stuckwisch has experience across a wide range of industries, including but not limited to waste and recycling.
Discussion by the Court
Recognized Methodology
The Defendants first challenged Stuckwisch’s expert report by arguing that she failed to follow any recognized methodology in calculating Sonrai’s alleged lost profits. The Court disagreed. It found that her report clearly laid out how she determined the length of Sonrai’s relationships with each customer, projected potential sales, and accounted for the costs of producing Vector units. She analyzed damages on a customer-by-customer basis—an approach the Court had previously deemed acceptable. As a result, the Court concluded that her methodology was valid and properly applied.
Damages Model
Next, the Defendants claimed that Stuckwisch’s damages model relied too heavily on a single, speculative assumption: that all five waste haulers would have adopted Vector across their entire fleets. But the Court had already addressed this point in its summary judgment ruling. It noted that Stuckwisch had explained the rationale behind her assumption and emphasized that it was up to the jury to weigh the credibility of that assumption. Her report referenced evidence from the waste industry showing that third-party companies had made commitments to install Vector fleetwide.
All-or-Nothing Approach
Lastly, the Defendants contended that Stuckwisch’s “all-or-nothing” approach to damages was flawed because she failed to consider other possible causes for Sonrai’s lost profits—something they argued was required under AICPA standards. In response, Stuckwisch clarified that her analysis again followed a customer-by-customer model: once a customer was lost, the associated revenue was lost entirely. The Court found this approach reasonable. It emphasized that Stuckwisch did not simply assume the Defendants caused the losses—she tied their conduct to Sonrai’s lost customers with specific reasoning and evidence.
Additional Incremental Operation Costs
Fourth, Defendants argued that Stuckwisch’s testimony was unreliable because her calculation of additional incremental operation costs, which are a necessary component of lost profits, was previously stricken and never included in any amended reports.
The Court agreed that Stuckwisch’s testimony would be unreliable without the deduction of additional incremental operation costs. But precluding Stuckwisch from testifying about those additional incremental operation costs was not the appropriate remedy. Instead, the proper path forward was to allow Stuckwisch to supplement her report and allow Defendants to depose her on the new report, and supplement their own rebuttal report if they wished.
Alternative Explanations
Finally, the Court issued this opinion following a hearing held on June 9, 2025, during which it preliminarily denied the Daubert motion. After that hearing, Stuckwisch submitted a supplemental report and sat for a deposition. On the first day of trial, the Defendants raised three new arguments to exclude her testimony.
First, they challenged Stuckwisch’s assumption that Sonrai would incur no cost for working capital. According to her, Chris Flood—Sonrai’s CEO—told her that his family’s business, which generated over $100 million in annual revenue, would cover Sonrai’s working capital needs. Defendants claimed this assumption was unfounded. However, the Court noted that the same assumption appeared in her 2021 report under the section on incremental operational costs. For the reasons already discussed, the Court declined to exclude her testimony on this basis.
Second, Defendants argued that Stuckwisch failed to consider an alternative cause: that Romano had the right to leave Sonrai at any time. But they did not explain how this constituted an “obvious alternative explanation” undermining the reliability of her analysis. The Court held that such arguments were better suited for cross-examination.
Third, the Defendants contended that Stuckwisch wrongly assumed that Vector faced no competition in the but-for world, effectively treating it as a monopoly product. She based this assumption on her understanding that no comparable product existed in the marketplace. The Court found this assumption to be reasonable, though it acknowledged that Defendants were free to challenge it during trial.
Held
The Court denied the Defendants’ Rule 702 motion to exclude the testimony of Suzanne Stuckwisch.
Key Takeaways:
- An expert need not rule out every alternative cause. Arguments about alternative explanations can be explored on cross-examination.
- Stuckwisch’s opinion reliably applies the lost profits principles and methodology to the facts of the case and the Court will not prejudge the ultimate correctness of her conclusions. Her reasoning satisfies Rule 702’s reliability standard. Defendants’ criticisms can be explored on cross-examination.
Case Details:
| Case Caption: | Sonrai Systems, LLC Et Al V. Anthony M. Romano Et Al |
| Docket Number: | 1:16cv3371 |
| Court Name: | United States District Court, Illinois Northern |
| Order Date: | June 20, 2025 |
