Exchange (also known as signing) is the point in an
acquisition when the parties enter into a binding share purchase
agreement (SPA) or asset purchase agreement (APA) by executing and exchanging the agreed contract, typically by exchange of counterparts (including electronically). It is a descriptive practice term rather than a statutory concept, but is widely used by practitioners across the UK and Ireland.
An acquisition agreement may provide for split exchange and
completion (a gap between signing and completion) or for simultaneous signing and completion. Where split, completion is conditional on the
satisfaction or waiver of conditions precedent, commonly including merger control or other regulatory approvals, shareholder or third‑party consents, financing, and pre‑completion reorganisation steps. Agreements usually include interim covenants, risk allocation provisions and a long‑stop date with termination rights if conditions are not met.
Usage is broadly consistent in England & Wales, Northern Ireland and Ireland (where “exchange of contracts” is also familiar from conveyancing). In Scotland, practitioners generally refer to signing/execution and conclusion of contract (and, in property, conclusion of missives). Execution in counterparts and delivery are facilitated by the Legal Writings (Counterparts and Delivery) (Scotland) Act 2015.