Aerospace suppliers sit at the top of the manufacturing multiple range because approvals take years to earn. The offsetting factor is program concentration, which buyers model directly against each platform's remaining life.
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AS9100 registration, NADCAP special-process approvals, customer supplier approvals, and a clean first-article and corrective-action history are the assets. A shop with those and older equipment consistently out-prices a better-equipped shop without them. The concentration analysis is what sets the final number: buyers build a program schedule with platform, position, rate history, and remaining production life, and they price the revenue accordingly. Change of control brings notification requirements, including to the Directorate of Defense Trade Controls where ITAR registration applies, and prime customers re-approve the supplier under the new entity documents. Sellers who map that sequence before diligence keep control of the closing schedule.