Completion, SPA protections and post-deal integration

In this final article of our Corporate Finance M&A insight series, we explain how to translate diligence findings into robust SPA protections, execute a smooth handover and deliver a structured integration that realises the value in your investment case.

The final stages of an acquisition – SPA negotiation, completion mechanics and post-deal integration – are where months of strategy, evaluation and diligence are either vindicated or undermined. It is a common misconception that the hard work is done once diligence is complete. In reality, the translation of diligence findings into precise SPA protections, the choreography of completion day and the rigour of post-deal integration are each critical to protecting and realising the value identified in your investment case.

The choice of pricing mechanism has practical implications for completion. Under a locked box, economic interest transfers from a fixed historical date. This requires robust leakage definitions and vendor undertakings and means the acquirer bears the risk of adverse movements between the locked-box date and completion. Under completion accounts, the purchase price is adjusted post-completion based on actual cash, debt and working capital at the completion date. This requires precise definitions, agreed accounting policies and a clear timetable for preparation, review and dispute resolution. 

Tax integration should not be left until after the first filing deadline. Early priorities often include integrating tax systems and policies, aligning VAT groups and payroll compliance, reviewing transfer pricing, updating intercompany agreements and simplifying the group structure where possible. Loss streaming rules should also be assessed so that historic losses are not inadvertently lost.

Where a smaller company is acquired by a larger group, the target may become subject to different corporation tax rules, including quarterly instalment payment obligations, and may need to align its tax governance and compliance processes with the wider group.

Where the buyer is an overseas group with existing UK operations, there may also be opportunities to review the UK tax grouping position, including loss utilisation, VAT grouping, interest deductibility and transfer pricing, even where the UK entities are not held under a single UK parent company.

The most frequent integration failures we observe stem from ambiguous authority structures that create decision bottlenecks, deferred integration decisions that undermine early momentum, earn-out conflicts arising from unclear accounting policies or disputes about the buyer's control rights and under-resourced integration teams that lack the bandwidth to execute alongside day-to-day operations. 

We support acquirers through SPA negotiation (accounting and tax), ensuring that value protection carries through to value realisation.

Approaching completion? Speak to our Corporate Finance team about converting your diligence findings into robust SPA protections