How goodwill arises
Suppose Company A acquires Company B for £500m. Company B’s balance sheet shows net identifiable assets (assets minus liabilities, restated to fair value) of £300m. The purchase price allocation (PPA) process identifies additional intangibles — customer contracts worth £80m, proprietary technology worth £60m — raising identified net assets to £440m. The residual £60m (£500m purchase price minus £440m identified net assets) is recorded as goodwill. This £60m represents what the buyer paid for things it could not specifically value: the assembled workforce, the reputation, the expected synergies. It sits on the balance sheet as an intangible asset indefinitely.
Impairment testing
Under US GAAP (ASC 350) and IFRS (IAS 36), goodwill must be tested at least annually for impairment at the reporting unit level. The test compares the carrying amount of the reporting unit (including goodwill) to its recoverable amount (the higher of fair value less costs to sell and value-in-use). If the carrying amount exceeds the recoverable amount, the difference is charged as an impairment loss — reducing the goodwill balance and hitting the income statement as a non-cash charge. Impairment is irreversible: once written down, goodwill cannot be restored even if the business recovers.
Why impairment signals overpayment
A goodwill impairment charge is management’s formal acknowledgement that the acquisition has not generated the value expected when the purchase price was set. The most common triggers: the acquired business has underperformed revenue and margin projections; expected synergies have not materialised; competitive dynamics have deteriorated; or the macro environment has worsened. Large impairments — HP’s $8.8bn Autonomy write-down, AOL/Time Warner’s $54bn charge — typically correlate with acquisitions made at the peak of market cycles at excessive multiples. Analysts scrutinise goodwill balances as a percentage of total assets and monitor impairment history when assessing management’s capital allocation track record.
“A goodwill impairment is not an accounting event — it is a CEO confessing, in numbers, that they overpaid.”
What this means for you
When evaluating companies that have made acquisitions, always examine the goodwill balance as a percentage of total equity and total assets. A company with goodwill equal to 50%+ of book equity has made large acquisitions at significant premiums — its book value is substantially composed of an asset whose real value is unverifiable until impaired. Goodwill-heavy balance sheets are common in media, software, and professional services sectors where acquired businesses lack tangible assets. The key analytical question is not whether goodwill exists, but whether the business has generated returns on the acquisition that justify the premium — measured by whether return on invested capital (including goodwill in the capital base) exceeds the cost of capital.