In 2005, Boeing sold one of its aircraft facilities to Spirit Aerospace and terminated the entire workforce at the facility of more than 10,000 workers. Spirit immediately rehired 8,354 of the workers, but a group of about 700 employees aged 40 and over who were not hired subsequently sued both companies for "pattern and practice" age discrimination.

In Apsley v. Boeing Co., the plaintiffs primarily relied on evidence that showed that Spirit's hiring decisions deviated from the expected norm by a statistically significant amount (i.e., 3 to 4 standard deviations). However, while the court found that this could constitute evidence of isolated or sporadic instances of age discrimination, it was not enough to show a pattern or practice of intentional age discrimination, i.e., that age discrimination was the company's "standard operating procedure." Key to the decision was that Spirit recommended and hired over 99% of the older employees that the company would have been expected to hire in the absence of any age discrimination, and that the percentage of older workers before and after the layoff was relatively similar (87.4% before and 86.6% after). The lawsuit was dismissed as to the pattern or practice age discrimination claim.