What does NEC4 clause 60.1(9) mean?

In the NEC4 main contract it is the Project Manager who withholds acceptance. On an NEC subcontract it is your main contractor. You often have to submit things for acceptance, such as a design, a subcontractor, a programme or proposed subcontract terms. For each, the relevant clause lists the reasons for not accepting it. Acceptance can be withheld for other reasons too, and this clause makes that a compensation event. To rely on it, show your submission, the reply withholding acceptance, the reason the reply gives, and that the reason is not one the relevant clause states. Where the reply gives no reason, you are weaker, because you then have to show what the real reason was. So first ask for the reason in writing. Notify under clause 61.3 within 8 weeks of becoming aware of the withheld acceptance. The change to the Prices, your contract price, is assessed under clause 63.1. It is the effect on actual Defined Cost up to the notification and forecast Defined Cost after it, plus the Fee. In practice that is the difference between what the refused proposal would have cost and what you had to do instead. You are expected to limit the damage by resubmitting or proposing an alternative quickly. Two things go wrong most. The refusal is dressed up in a stated reason the facts do not support, and you accept it without challenge. Or a programme is refused for a stated reason, and you try to use this clause when the real complaint lies elsewhere. Any delay to the Completion Date is assessed separately under clause 63, and that is a job for your planner.