Effectivity

Also called date effectivity, serial effectivity, lot effectivity

Effectivity says from when a part or BOM change applies: from a date, a serial number, a lot or a unit. It lets a change be released in engineering while production keeps building the current version until the cut-in point.

Without effectivity, a released change is either in or out everywhere at once, which rarely matches reality. A plant may need to use up stock, or a customer contract may fix the configuration for certain units.

Windchill supports date, serial number and lot effectivity. Serial and unit effectivity matter most in aerospace and defense, where each delivered unit’s configuration has to be known.

Related terms

Change notice
Configuration management
As-built vs as-maintained

Go deeper

As-Built vs. As-Maintained: The Configuration Gap That Costs Aerospace Real Money
EBOM vs MBOM: What's the Difference and Why It Matters

Last reviewed November 2026 by Element Consulting

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