Every plan sponsor owns a plan document. Very few read it. Fewer understand it. And almost none use it as the operating manual it was designed to be.
Instead, many rely on “tribal knowledge”, the memory of someone in HR who has been there since the Clinton administration. That’s how operational errors happen. The plan document governs eligibility, contributions, vesting, loans, QDROs, and distributions. If you operate differently than the document dictates, it’s not “close enough.” It’s a compliance failure.
Plan sponsors should review the document annually, especially after mergers, acquisitions, or workforce changes. Make sure operations match the words on paper. When in doubt, ask the TPA or ERISA counsel. A plan document isn’t meant to sit on a shelf. It’s meant to keep you out of trouble.