Subsections (3) to (6) apply if— a conciliation officer— has taken action under section 18 in a case, and issues a certificate in writing stating that a compromise has been reached in the case, and all of the terms of the compromise are set out— in a single relevant document, or in a combination of two or more relevant documents. A document is a “ it is the certificate, or it is a document that is referred to in the certificate or that is referred to in a document that is within this paragraph. Any sum payable by a person under the terms of the compromise (a “compromise sum”) shall, subject to subsections (4) to (7), be recoverable— in England and Wales, by execution issued from a county court or otherwise as if the sum were payable under an order of that court; in Scotland, by diligence as if the certificate were an extract registered decree arbitral bearing a warrant for execution issued by the sheriff court of any sheriffdom in Scotland. A compromise sum is not recoverable under subsection (3) if— the person by whom it is payable applies for a declaration that the sum would not be recoverable from him under the general law of contract, and that declaration is made. If rules of court so provide, a compromise sum is not recoverable under subsection (3) during the period— beginning with the issue of the certificate, and ending at such time as may be specified in, or determined under, rules of court. If the terms of the compromise provide for the person to whom a compromise sum is payable to do anything in addition to discontinuing or not starting proceedings, that sum is recoverable by him under subsection (3)— in England and Wales, only if a county court so orders; in Scotland, only if the sheriff so orders. Once an application has been made for a declaration under subsection (4) in relation to a sum, no further reliance may be placed on subsection (3) for the recovery of the sum while the application is pending. An application for a declaration under subsection (4) may be made to an employment tribunal, a county court or the sheriff. Employment tribunal procedure regulations may (in particular) make provision as to the time within which an application to an employment tribunal for a declaration under subsection (4) is to be made. Rules of court may make provision as to— the time within which an application to a county court for a declaration under subsection (4) is to be made; the time within which an application to the sheriff for a declaration under subsection (4) is to be made; when an application (whether made to a county court, the sheriff or an employment tribunal) for a declaration under subsection (4) is pending for the purposes of subsection (7). Nothing in this section shall be taken to prejudice any rights or remedies that a person has apart from this section. In this section “compromise”
(except in the phrase “compromise sum”) means a settlement, or compromise, to avoid proceedings or bring proceedings to an end.