Deal Autopsy: Three Days From Completion, a Tax Liability Nobody Had Seen. Here Is How We Saved the Deal.

All details in this account have been anonymised. The sector, individuals, and specific figures have been changed to prevent identification. The sequence of events, the nature of the liability, the resolution mechanics, and the lessons are drawn from a real situation.

The previous deal autopsies in this series have been, in different ways, cautionary — transactions that went wrong, that produced worse outcomes than they should have, or that collapsed under the weight of problems that proper preparation would have avoided. This one is different. This is the deal that should have died and did not — because the people involved handled a genuinely difficult late-stage problem with the speed, creativity, and relationship quality that the situation demanded.

It is worth telling this story because the lessons run in both directions. The problem that emerged was serious and had not been found in months of due diligence. That is a lesson. The way it was resolved — the specific mechanics, the relationship dynamic, and the adviser quality that made a solution possible — is an equally important lesson. Late-stage problems in acquisitions are more common than most buyers and sellers expect. How they are handled determines the outcome.

The Context

The business was a manufacturing business in the north of England. Revenue of just over £3.8m, EBITDA of approximately £470k on a normalised basis, and a business that had been trading for twenty-six years under the same family ownership. The current owner — the founder's son, who had taken over the business fifteen years earlier — was selling because he wanted to move into a different phase of life and had no family member interested in succession.

The deal had been running for six months. Price agreed at just under £2.4m. Structure: a combination of senior debt, personal equity from the buyer, and a modest vendor loan of £150k over three years. Due diligence had been thorough. Legal documentation was substantially agreed. Exchange was scheduled for a Thursday, with completion to follow seven days later. The deal had been professionally managed on both sides.

On the Monday morning of exchange week — three days before the scheduled exchange — the buyer's tax adviser made a discovery.

The Discovery

As part of a final pre-exchange review, the buyer's tax adviser was reviewing the company's corporation tax records for the past six years. The review had been completed earlier in the due diligence process, but a specific query about a capital asset disposal in year four of the review period had prompted a closer look at the underlying calculation.

What emerged was a discrepancy between the disposal proceeds recorded in the corporation tax return for that year and the proceeds documented in the company's own accounting records. The disposal concerned a piece of manufacturing equipment that had been sold to a third party. The proceeds in the CT return were £42k lower than the proceeds in the company's management accounts for the same period.

The explanation, which the seller's accountant provided the same afternoon when asked directly, was this: a portion of the disposal proceeds — £42k — had been paid in cash directly to the seller's father, the original founder, who had retained an informal interest in the specific piece of equipment since the family transferred the business to the current owner. This cash payment had been agreed informally, had not been run through the company's accounts, and had therefore not been included in the corporation tax return for the year in which the disposal occurred.

The buyer's tax adviser's immediate assessment: this was undeclared income in the company's corporation tax return, likely constituting tax evasion rather than mere tax avoidance. The quantum — corporation tax on £42k at the applicable rate, plus interest and potential penalties — was approximately £12k to £15k in the base case. But the more serious issue was what HMRC would do if the discrepancy were discovered. In a share purchase, the buyer acquires the company including its historical tax liabilities. If HMRC investigated and concluded that the returns had been fraudulently prepared, the exposure could be significantly higher — and the company's relationship with HMRC for subsequent years would be permanently damaged.

The Next Thirty-Six Hours

The discovery landed at approximately 3pm on Monday. Exchange was scheduled for Thursday morning. The buyer's advisers needed to decide how to handle it, and quickly.

The first conversation — between the buyer's tax adviser and the buyer — covered three options. First, withdraw from the transaction entirely: the discovery constituted a breach of the tax warranties the seller had given in the SPA, and the buyer could argue that the discovery justified terminating the agreement. Second, proceed to exchange but exclude the specific tax liability through a targeted indemnity, requiring the seller to fund any HMRC claim relating to the undisclosed disposal. Third, renegotiate the price to reflect the risk — adjust the consideration downward by an amount that priced the contingent liability into the deal.

The buyer's instinct was to proceed if a workable solution could be found. The business was good. Six months of work had been invested. The management team were committed and the vendor finance arrangement reflected the seller's genuine confidence in the business. Walking away over a £12k to £15k contingent liability, while technically justifiable under the warranty provisions, felt disproportionate.

But the second and third options each had a problem. A targeted indemnity was straightforward in theory — the seller agrees to pay the buyer pound for pound for any HMRC claim arising from the specific disclosure — but it depended on the seller having the financial capacity to meet that indemnity if it crystallised. A price reduction, meanwhile, did not address the tax risk directly: it reduced the consideration but left the company still carrying an undisclosed historical liability that could affect its relationship with HMRC for years.

The solution that the buyer's tax adviser proposed — and that was eventually agreed — was more creative than either of those options.

The Resolution Mechanics

The proposed solution had three components, each addressing a different dimension of the problem.

Component 1: Voluntary disclosure to HMRC

The seller agreed, as a condition of the deal proceeding, to make a voluntary disclosure to HMRC before exchange covering the undisclosed disposal proceeds. A voluntary disclosure — where a taxpayer proactively identifies and corrects an error in their tax returns — is treated significantly more favourably by HMRC than a liability discovered through investigation. The tax, interest, and any penalty are paid, but the penalty rate for voluntary disclosure is substantially lower than for a prompted investigation, and the reputational relationship with HMRC is preserved rather than damaged.

The voluntary disclosure was prepared by the seller's tax adviser and submitted to HMRC's digital disclosure service on the Tuesday — two days before the scheduled exchange. HMRC's digital disclosure service typically acknowledges receipt within 24 to 48 hours and provides a reference number that can be cited in the SPA as evidence that the liability has been identified and is being regularised.

The total liability calculated in the voluntary disclosure — corporation tax, interest, and a reduced penalty rate — came to £14,200. This was a manageable and specific number rather than an open-ended contingent liability.

Component 2: Escrow arrangement at completion

Rather than reducing the headline price — which would have required renegotiating the vendor finance terms and the senior debt facility at a point when neither party had time for that — the parties agreed to an escrow arrangement. A sum of £20,000 was held in escrow by the buyer's solicitors at completion, to be released to the seller once HMRC had formally confirmed closure of the voluntary disclosure.

The escrow amount was set above the calculated liability — £20k versus the calculated £14.2k — to provide a buffer for any additional interest or penalties that might crystallise between submission and formal HMRC closure. The seller received the full consideration at completion minus the escrow amount, with the escrow released once the voluntary disclosure was closed.

This structure gave the buyer certainty that the liability would be funded — the escrow sat with the buyer's solicitors, not with the seller — while giving the seller a clear path to releasing the full consideration once the matter was resolved.

Component 3: A specific tax warranty and indemnity

Alongside the voluntary disclosure and the escrow arrangement, a specific indemnity was added to the SPA covering any HMRC claim arising from the specific disposal that was not captured by the voluntary disclosure — to protect against the risk that HMRC opened a broader investigation and discovered additional issues in the same period. The indemnity was secured against the vendor loan, which was already documented and in place: if the indemnity was called, the amount would be deducted from the outstanding vendor loan balance rather than requiring a separate cash payment from the seller.

This last element was the creative solution that made the overall structure work. The seller had already provided vendor finance of £150k. That vendor loan became the security for the indemnity — the buyer had a clear and immediately enforceable remedy if the liability exceeded the escrow and the seller needed to fund the difference. No additional security was required and no new negotiation was opened on the financing structure.

Exchange and Completion

Exchange happened on Thursday as originally scheduled, forty-eight hours after the voluntary disclosure was submitted. Completion followed the following week. The deal — six months in the making — completed on the original timeline, at the original price, with the addition of the escrow arrangement and the specific indemnity.

The voluntary disclosure was formally closed by HMRC eleven weeks after submission. HMRC accepted the disclosure, calculated the final liability at £13,800 — slightly below the estimate — and confirmed that no further investigation of the specific disposal was intended. The escrow was released to the seller at that point. The total financial impact on the seller was the £13,800 HMRC liability and the eleven-week deferral of the escrow amount. The total financial impact on the buyer was eleven weeks of holding £20,000 in solicitors' escrow.

By the standards of late-stage deal problems, this was resolved remarkably cleanly. It required speed, creativity, and a relationship between buyer and seller that was strong enough to survive a significant and unexpected complication three days before exchange.

What Made This Resolution Possible

The buyer's tax adviser caught it before exchange, not after

The most important element of this story is the timing of the discovery. If the discrepancy had been found after completion — in a post-completion review, in an HMRC investigation, or in the due diligence for a subsequent sale — the situation would have been significantly worse. The buyer would have owned the liability with no clean legal mechanism to recover it from the seller, and the voluntary disclosure process would have been substantially more complicated.

The pre-exchange discovery was not the result of the initial due diligence — it emerged from a final pre-exchange review triggered by a specific query. That review was not mandatory or standard in the process. The buyer's tax adviser chose to do it as a belt-and-braces exercise in the final week. That choice — and the adviser's technical depth in identifying a small discrepancy in a large volume of historical records — made the difference between a clean deal and a post-completion problem of uncertain magnitude.

The lesson: the due diligence process is not finished until exchange. A final pre-exchange review by the tax adviser, even a targeted one focusing on specific areas of risk identified earlier in the process, is worth the cost.

The buyer did not immediately reach for the exit clause

The buyer's instinct on Monday afternoon was not to walk away. It was to find a solution. That instinct was commercially sound — the business was good, the relationship was solid, and the liability was specific and manageable — but it was also an emotional choice that required the buyer to stay calm under significant pressure.

A buyer who had panicked — who had instructed their solicitors to invoke the warranty breach and begin withdrawal proceedings immediately — would probably have lost the deal without exploring whether a workable solution existed. The liability was real, but it was not so large or so uncertain that a reasonable buyer, with good advisers and a good relationship with the seller, could not find a way through it.

The discipline of assessing the actual severity of the problem clearly — rather than responding to the shock of the discovery — was what created the space for the solution.

The seller engaged honestly and constructively

When the buyer's team presented the discovery to the seller, his response was honest. He confirmed the situation, explained the background — the informal arrangement with his father that had predated the formal transfer of the business — and expressed a genuine desire to find a solution that allowed the deal to complete. He did not become defensive, did not attempt to minimise the significance of the discovery, and did not instruct his advisers to dispute the buyer's tax adviser's analysis.

That honesty was not just admirable — it was commercially essential. A seller who disputed the finding, delayed the conversation, or tried to characterise the issue as less significant than it was would have consumed the time that the solution required. The voluntary disclosure process is fast, but it requires the seller to engage immediately. A 48-hour window between discovery and exchange left no room for denial.

The relationship that had been built over six months of professional, respectful dealing was the foundation that allowed the seller to respond this way. A deal where the relationship had been adversarial, or where trust had been damaged in the negotiation, would have produced a different response at exactly this moment.

The advisers found a creative solution under time pressure

The voluntary disclosure plus escrow plus vendor loan security structure was not an off-the-shelf solution. It was assembled in real time, by advisers who understood the specific mechanics of each component and who could see how they fitted together in the specific context of this deal. A tax adviser who did not know the voluntary disclosure process in detail. A solicitor who had not handled escrow arrangements in a compressed timeline. A buyer who did not have vendor finance already in place — all of those would have produced a worse outcome.

The quality of the adviser team was not incidental to the resolution. It was essential to it. The lesson for any acquisition entrepreneur: your advisers are not just a cost. They are the people who determine whether a late-stage problem is resolved or whether it ends the deal.

The Patterns This Deal Represents

Late-stage discoveries in acquisitions are more common than the official narrative of due diligence suggests. Due diligence, however thorough, is a sampling exercise — it cannot review every document, test every number, and chase every discrepancy in the historical records of a business. Things are missed. Sometimes those things are trivial. Sometimes they are material.

What determines whether a material late-stage discovery ends the deal or is resolved constructively is not primarily the severity of the issue. It is the quality of the relationship between buyer and seller, the capability of the adviser team on both sides, and the commercial orientation of the parties — whether they approach the problem as something to solve or as a reason to exit.

The deals that survive late-stage problems are almost always the ones where both parties genuinely want the transaction to complete and where they have built the relationship and the adviser infrastructure that makes a solution findable. The ones that collapse over late-stage problems are often the ones where the relationship was already fragile, where the advisers were too cautious or too slow, or where one party used the problem as a convenient exit from a deal they were already uncertain about.

Download the Dealwise Due Diligence Red Flag Checklist — including the tax due diligence section — to ensure your pre-exchange review covers the specific areas most likely to produce late discoveries.

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