Attrition Rate: Embedding Technological Obsolescence into Intangible Asset Valuation

Introduction: the attrition rate, the forgotten parameter in valuing technology assets

When a valuation expert appraises a pharmaceutical patent, a proprietary software programme or a SaaS publisher, one question conditions the entire exercise: what is the real economic life over which the asset will generate cash flows? The legal life of a patent is twenty years, a software licence can run in perpetuity, and a SaaS contract renews automatically. Yet in all three cases the economic value declines well before legal expiry — under the effect of technological obsolescence, the arrival of competing generations, customer churn or migration toward alternative architectures.

The attrition rate — sometimes called the erosion, churn or obsolescence rate — formalises this gradual decline of economic advantage. Conceptualised in France by Pierre Breesé and Alain Kaiser in L'évaluation financière des droits de propriété intellectuelle (Gualino, 2010), it is now embedded in the professional methodologies for valuing intangible assets, in the IAS 38 framework (useful life accounting for obsolescence) and in the International Valuation Standards (IVS 210) on intangible assets.

« An entity shall assess whether the useful life of an intangible asset is finite or indefinite […] taking into account all relevant factors, in particular technical, technological, commercial or other types of obsolescence. » — IAS 38.88-90, IFRS Foundation.

In a tech market where innovation cycles are compressing (five to seven years for a pharma patent, three to five years for a SaaS platform, eighteen to thirty-six months for an artificial-intelligence model), where private equity funds demand valuations defensible before Big Four auditors, and where the French or Swiss tax authorities scrutinise intragroup transfer pricing on intellectual property, ignoring the attrition rate amounts to mechanically overvaluing the asset and weakening the transaction.

This article reviews the definition of the attrition rate, its methodological origin with Breesé-Kaiser and its IFRS anchoring, the concrete reasons that justify integrating it, the calibration methodology, the situations where it becomes unavoidable, the profile of the expert to mandate, two quantified case studies (a Swiss pharma patent and a B2B mid-market SaaS), the executive's perspective, ten frequently asked questions and an operational summary.

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Definition: what is the attrition rate of a technology asset?

The attrition rate of a technology asset is the annual percentage decline in the economic value or the cash flows generated by the asset, under the effect of technical obsolescence, competition by substitution, customer churn or contractual erosion. Applied to patents, it reflects the progressive loss of competitive advantage against newer technological generations. Applied to software and SaaS contracts, it captures the natural departure of customers toward competing solutions or more modern architectures.

Concretely, in a discounted cash flow (DCF) model, the attrition rate is applied to the projected flows upstream of the discount rate. For an asset generating 1 MCHF in the first year with an attrition rate of 8%, the second-year flow falls to 0.92 MCHF, the third-year flow to 0.85 MCHF, and so on — independently of the organic growth of the market, which must be the subject of a separate projection.

The attrition rate is distinct from three neighbouring parameters that must not be confused. The discount rate (or WACC) reflects the cost of capital and the general risk premium, but does not break out the specific risk of technological obsolescence. The accounting amortisation period spreads the acquisition cost of the asset linearly over its estimated useful life, without reflecting the economic non-linearity of the decline. The residual legal life (twenty years for a patent, indefinite for software) is an absolute upper bound, rarely representative of economic reality. The attrition rate therefore complements — and does not replace — these three parameters.

Origin: from the Breesé-Kaiser framework to IFRS and IVSC normalisation

The attrition rate applied to intangible assets was conceptualised in France by Pierre Breesé, president of IP TRUST and a recognised expert in intellectual-property valuation, and by Alain Kaiser, a sworn expert before the Paris Court of Appeal. Their reference work, L'évaluation financière des droits de propriété intellectuelle — Brevets et Actifs technologiques (Gualino, first edition 2010), structures for the first time in the French language the methodology for integrating an attrition rate into the valuation of a patent or a technology licence. The book formalises a now-classic distinction between the legal life, the economic life and the useful life of an intangible asset — a distinction without which valuation produces systematically biased results.

On the normative front, the IFRS framework has progressively incorporated the logic of attrition through IAS 38 (intangible assets), which requires the entity to assess the useful life of an intangible asset by explicitly accounting for factors of technical, technological and commercial obsolescence (IAS 38.88-90). The IVS 210 framework of the International Valuation Standards Council (IVSC), applicable to independent valuation engagements, explicitly recommends accounting for an attrition factor when the value of an intangible asset is derived from future cash flows, and specifies that an empirical justification must be documented.

In Switzerland, the Federal Tax Administration (ESTV) recognises the need to weight the value of technology assets by an economic-life factor in intragroup operations and transfer pricing on intellectual property, in line with the OECD transfer pricing principles. In France, the tax doctrine and the case law of the Conseil d'État have for several years admitted the discount for technological obsolescence in the valuation of intangible assets transferred or sold.

Why integrate an attrition rate in valuation

The attrition rate fulfils five complementary functions that, on their own, justify the calibration effort required to integrate it into a valuation model.

Firstly, it restores consistency between legal life and economic life. A pharmaceutical patent registered today for twenty years will generate significant flows only for ten to twelve years on average, after which generics, next-generation molecules and the evolution of therapeutic protocols erode the commercial advantage. Without an attrition rate, the DCF artificially stretches the flows over the legal life and overvalues the patent by 25% to 40% depending on the therapeutic class.

Secondly, it incorporates the sectoral asymmetry of obsolescence. A mechanical industrial process patent may retain a stable economic value for fifteen years; a software patent or an artificial-intelligence algorithm loses 60% to 80% of its value within five years against the following generations. An attrition rate differentiated by technology class reflects this reality, where a single discount rate flattens it.

Thirdly, it secures tax defensibility. The French and Swiss tax authorities regularly contest the valuations of intangible assets presented in intragroup operations (contributions, disposals, licence royalties), on the grounds that they overstate the duration of future benefits. A valuation explicitly discounted by a documented attrition rate withstands tax challenge better than a linear, unadjusted valuation.

Fourthly, it aligns the valuation with the practice of Big Four auditors. During a Purchase Price Allocation (PPA) following an acquisition or an impairment test under IAS 36 / FER 27, IFRS auditors now require an explicit justification of the finite or indefinite useful life of intangible assets, with an analysis of obsolescence factors. The attrition rate provides the quantitative framework for that justification.

Fifthly, it structures the M&A negotiation. In the disposal of a SaaS publisher, a biotech or a patent portfolio, the acquirer systematically applies an implicit attrition rate in its business case. The seller who ignores this parameter in its target valuation enters the negotiation with a benchmark naively higher than the market price, and concedes successive discounts instead of structuring a balanced discussion around the right parameter.

How an attrition rate is built

The calibration of an attrition rate relies on a six-step methodology, consistent with the professional practice codified by Breesé-Kaiser and aligned with the IVSC standards.

The expert begins by characterising the asset: nature (patent, software, customer base, technology brand, trade secret), residual legal life, geographic scope of protection, technology class. This characterisation determines the reference window for the obsolescence analysis. A pharmaceutical molecule patent in oncology does not obey the same dynamics as a SaaS software-method patent or a mechanical industrial process patent.

Next comes the analysis of obsolescence factors. The expert identifies the specific vectors of decline: anticipated entry of generics, competing patents being filed, evolution of technical standards (5G to 6G, GPT-4 to GPT-5, ARM to RISC-V), regulatory changes (health-agency recommendations, ESG standards, GDPR) and substitution by disruptive technologies (artificial intelligence, blockchain, photonics). For a SaaS, the vectors are gross churn, net churn, the evolution of architectures (monolithic → microservices → serverless) and changes in business model (perpetual licence → subscription → usage-based).

The expert then proceeds to empirical calibration. For a patent, the expert relies on the historical sales curves of comparable molecules or technologies once they have been genericised or substituted, on patent citation analyses (a declining citation rate as a proxy for the erosion of advantage), and on published sectoral benchmarks (notably those compiled by IP valuation firms such as IP TRUST, BV4 or Aon). For a SaaS, the expert relies on gross-churn benchmarks (1% to 5% per month for SMB, 0.5% to 2% for mid-market, < 1% for enterprise) and on cohort-retention curves specific to the segment.

The expert structures the attrition rate within the DCF model. The rate may be constant (8% per year over ten years) or variable (3% for the first three years, 8% for years 4-7, 15% for years 8-10 to model the acceleration of post-peak decline). The variable variant is generally more defensible because it better reflects the empirical curves, but it requires finer documentation. The rate is applied upstream of the WACC and is never cumulated with an additional technological risk premium in the discount rate, on pain of double counting.

The expert carries out sensitivity tests. The expert varies the attrition rate by plus or minus two percentage points relative to the central scenario, and measures the impact on the final value. For a typical technology asset, a 2% variation in the attrition rate changes the valuation by 15% to 25%. This analysis identifies the parameter as a key variable of the model and justifies its detailed documentation in the report.

Finally, the expert documents consistency with the other parameters. The expert verifies that the attrition rate retained is not redundant with a technological risk premium applied to the WACC, that it is not in contradiction with the accounting amortisation period adopted by the entity, and that it is consistent with the assumptions of organic growth of the underlying market. This documentation constitutes the central evidentiary piece in the event of tax challenge or audit.

When to use the attrition rate

Several situations make the integration of an attrition rate either technically mandatory or strongly recommended in view of good valuation practice.

During any Purchase Price Allocation (PPA) following the acquisition of a software publisher, biotech, medtech or technology company, the attrition rate conditions the finite useful life of the recognised intangible assets (patents, developed technologies, customer base, recurring contracts) and therefore the amortisation schedule over ten or fifteen years, as well as the residual portion of unallocated goodwill.

During an annual impairment test under IAS 36 or Swiss GAAP FER 27, the attrition rate adopted at the initial PPA must be re-examined in light of the effective evolution of the flows and the competitive environment. A significant gap between initial projections and observed reality signals an indicator of impairment that may lead to a material write-down of goodwill or intangible assets.

During a partial or total disposal of a patent portfolio or a technology licence, the attrition rate determines the value of the discounted future royalties and therefore conditions the sale price. The practice of patent transactions between major American and Asian tech players (Google, IBM, Samsung) systematically integrates an explicit attrition rate, often between 5% and 15% per year depending on the technology class.

During an intragroup transfer-pricing operation on intellectual property — contribution of a patent to a company, intercompany licence royalty, intra-group sale of an IP portfolio — the French or Swiss tax authority requires economic documentation that explicitly includes the justification of the duration of future benefits. The attrition rate has become a standard component of this documentation, in line with the OECD principles.

Finally, during a pre-disposal valuation of a SaaS publisher or a technology scale-up, the technology attrition rate adds to the classic customer churn a prospective discount for the evolution of architectures, the arrival of generative AI in the segment or sectoral consolidation. A contemporary SaaS valuation now integrates this dual dimension almost systematically.

Who to call on

The choice of the technology-asset valuation expert directly conditions the defensibility of the attrition rate adopted and, by extension, the final valuation. Three criteria should guide the selection.

Firstly, technology sector expertise. The calibration of the attrition rate requires a fine understanding of the obsolescence dynamics of the sector concerned — biotech, medtech, B2B SaaS, software infrastructure, semiconductors, artificial intelligence. A generalist expert will apply sectoral benchmark rates without accounting for the specifics of the asset valued, producing a statistically plausible but operationally wrong result. The ideal expert has already conducted comparable engagements in the same sub-segment, and masters the reading of patent citation analyses, cohort-retention curves or IDC/Gartner benchmarks on technology cycles.

Secondly, multi-referential methodological mastery. The expert must articulate, in a consistent manner, the attrition rate with the WACC, with the accounting amortisation period adopted, and with the assumptions of market growth. The expert must also know how to choose between the relief-from-royalty approach, the excess-earnings method (multi-period excess earnings method, MEEM) and the replacement-cost approach (cost approach) depending on the nature of the asset. The intangible-asset valuation methodology deployed must align with the IVSC standards and the Breesé-Kaiser doctrine for IP assets.

Thirdly, the ability to defend the conclusions before auditors and the tax authority. A technology-asset valuation report serves successively as support for the PPA, the annual impairment test, the transfer-pricing documentation and, where applicable, a tax dispute. The expert must be able to explain the calibration of the attrition rate to a Big Four statutory auditor, a tax inspector or a judge, with precise empirical and bibliographic references (Breesé-Kaiser, IAS 38, IVS 210, OECD).

Hectelion works on the valuation of technology assets for SaaS publishers, biotechs, medtechs, deep tech scale-ups and franco-Swiss industrial groups, drawing on its dual franco-Swiss expertise, its multi-method methodology aligned with the IVSC standards and the Breesé-Kaiser doctrine, and its economic independence from traditional financial intermediaries. The firm's practice covers PPA engagements following acquisitions, annual impairment, intragroup transfer pricing and pre-disposal valuation on intangible assets whose unit value is between 2 and 500 MCHF. Each engagement gives rise to detailed documentation of the attrition rate adopted, with sensitivity analysis and sectoral empirical justification.

Advantages: DCF precision, tax defensibility and IFRS alignment

Integrating a documented attrition rate brings five structuring advantages to the valuation of a technology asset. The first advantage is the precision of the DCF model: the temporal profile of the flows better reflects the observed economic reality, and the net present value converges toward the transaction prices observed on the secondary market for comparable assets.

The second advantage is tax defensibility: the French or Swiss tax authority, when it contests a valuation, attacks first and foremost the absence of any accounting for obsolescence. A report explicitly documented on this point withstands tax challenge better and limits the risk of a material reassessment.

The third advantage is IFRS / FER alignment. The documentation of the attrition rate provides the quantitative justification required by IAS 38 on the useful life of intangible assets, and facilitates the work of the statutory auditor during the annual close and the IAS 36 / FER 27 impairment test.

The fourth advantage is consistency with market benchmarks. The transaction multiples observed on SaaS publishers, biotechs and IP portfolios implicitly incorporate an average attrition rate; making this parameter explicit in the valuation allows one to understand why a specific target trades above or below the sectoral average.

The fifth advantage is the structuring of the M&A negotiation. Seller and acquirer can debate rationally about the calibration of the attrition rate — does the projection span seven or ten years? is the rate constant or variable? — rather than clashing over an opaque price range with no objectifiable parameter.

Limitations: double counting, empirical calibration and sectoral asymmetry

The attrition rate has four limitations that it is advisable to identify ahead of the valuation engagement. The first limitation is the risk of double counting with the discount rate: if the WACC adopted already integrates a high technological risk premium (for example via a tech sector beta above 1.5 or a specific risk premium of 3% to 5%), the application of an additional attrition rate mechanically compresses the value twice for the same risk. This methodological error, frequent among inexperienced experts, can produce an undervaluation of 20% to 35%.

The second limitation is the difficulty of empirical calibration. Historical data on technological obsolescence is rarely available publicly, especially for niche segments or emerging technologies (generative artificial intelligence, photonics, quantum computing, synthetic biology). The expert must then resort to imperfect proxies — retention curves of neighbouring cohorts, patent citation rates, benchmarks published by the large IP valuation firms — and explicitly document the assumptions adopted.

The third limitation is sectoral asymmetry. An attrition rate relevant for a pharmaceutical patent in oncology (8% to 12% per year post-peak) is not relevant for a cloud-native software patent (15% to 25% per year), nor for a mechanical industrial process patent (2% to 5% per year). The expert must resist the temptation to apply a single transversal rate to a heterogeneous portfolio, and instead disaggregate the analysis by technology class — a time-consuming but indispensable operation for complex portfolios.

The fourth limitation lies in the prospective and therefore uncertain nature of the exercise. The attrition rate projects a dynamic of obsolescence over five to fifteen years, in an environment where technological ruptures (the arrival of generative AI models in 2022-2024 being the example) can invalidate any projection within two to three years. The valuation report must therefore systematically integrate an annual review clause and a sensitivity analysis broadened to technological-rupture scenarios.

The 5 mistakes to avoid

Mistake 1: Confusing the legal life and the economic life of the asset

The most frequent mistake consists in projecting the flows of a patent over its residual legal life (for example fifteen years for a patent filed five years ago) without applying any obsolescence discount. In pharmaceutical, biotech or software practice, the economic value of a patent declines significantly from the fifth or seventh year, long before legal expiry. This confusion leads to a systematic overvaluation of 25% to 40% depending on the technology class. The rule is simple: the legal life is an absolute upper bound, never the relevant horizon of the DCF model.

Mistake 2: Double counting with the discount rate

The expert sometimes applies simultaneously a high technological beta in the WACC and a separate attrition rate on the flows. This double penalisation for the same risk undervalues the asset by 20% to 35%. The strict methodological rule is that one of the two parameters must absorb the technological obsolescence, never both together. The professional practice codified by Breesé-Kaiser and aligned with IVSC favours the explicit application of the attrition rate on the flows, with a WACC reflecting only the general cost of capital and the market risk premium.

Mistake 3: Applying a constant attrition rate over the entire horizon

A constant attrition rate of 8% per year over ten years is generally empirically wrong. The observed reality shows inverted-S curves: slow decline in the first years (the technological advantage is still active), abrupt acceleration at the moment of arrival of direct competitors or generics, then residual flattening at the end of life. A more defensible model integrates a variable rate by phase (for example 3% years 1-3, 10% years 4-7, 18% years 8-10), reflecting this three-stage dynamic.

Mistake 4: Ignoring maintenance and incremental innovation

A technology asset is not a static resource: the software publisher invests in continuous R&D, the patent holder files continuation patents, the technology-brand owner runs repositioning campaigns. This incremental innovation slows the observed attrition and may justify a rate well below the gross sectoral benchmarks. The expert must therefore isolate the net attrition (after accounting for maintenance R&D) from the gross decline, consistently with the flows adopted in the DCF.

Mistake 5: Neglecting sectoral benchmarks and empirical data

Adopting an attrition rate by intuition or by implicit alignment on a peer's practice, without documented empirical reference, weakens the valuation report. The benchmarks published by the specialised IP firms (IP TRUST, BV4, Aon, Houlihan Lokey), the sectoral reports (IDC, Gartner, EvaluatePharma) and the case-study databases (notably IP TRUST for French practice) must be systematically consulted and cited. Failing that, the report is exposed to tax challenge or to being called into question by the auditor.

Case 1 : Swiss pharmaceutical patent, valuation of 5.3 MCHF with attrition versus 7.5 MCHF without

In 2025, a Swiss biotech specialised in targeted oncology holds a patent on a molecule in advanced phase II clinical trials, with a residual legal life of fourteen years. The company is preparing a licence disposal to a major European pharmaceutical laboratory and mandates an independent expert to produce a valuation report defensible before the acquirer and the Swiss tax authority.

The projected royalty flows are 1.3 MCHF per year for the first five years (commercial ramp-up expected post-marketing authorisation), 0.85 MCHF per year for years 6 to 10 (cruising regime) and 0.4 MCHF per year for years 11 to 14 (decline linked to the arrival of generics). The WACC adopted, specific to the European mid-cap biotech sector, stands at 10% and reflects the general cost of capital without integrating any additional technological risk premium.

A first valuation, conducted without an explicit attrition rate, discounts the nominal flows at 10% over fourteen years and concludes at a net present value of 7.5 MCHF. The independent expert judges this valuation overstated because it ignores the intra-period erosion dynamic linked to the continuation patents filed by direct competitors and to the anticipated arrival of next-generation molecules in targeted oncology from the eighth year.

The expert therefore applies a variable attrition rate in line with the Breesé-Kaiser practice: 5% per year in years 1-3 (the technological advantage is protected by regulatory exclusivity, but early competitive pressure remains real in targeted oncology), 12% per year in years 4-7 (entry of the first direct competitors) and 22% per year in years 8-14 (erosion accelerated by generics and next-generation molecules). After applying this attrition rate to the projected flows, the net present value falls to 5.3 MCHF, a discount of 29% relative to the gross valuation.

The sensitivity analysis shows that a variation of plus or minus two points on the attrition rate in years 4-7 changes the valuation by plus or minus 12%, confirming the central character of this parameter. The biotech ultimately retains the discounted valuation of 5.3 MCHF in its report, negotiates on this basis with the acquirer (which initially offers 4.5 MCHF but accepts 5.1 MCHF after challenge on the attrition rate in years 8-14), and documents consistency with the OECD principles on transfer pricing to anticipate the post-closing tax due diligence. The transaction is secured and the documentation of the attrition rate becomes a central piece of the tax file.

Case 2 : Franco-Swiss B2B SaaS publisher, valuation of 60 MCHF with attrition versus 72 MCHF without

A franco-Swiss B2B SaaS publisher specialised in supply-chain management for industrial mid-caps achieves in 2025 an annual recurring revenue (ARR) of 12 MCHF, with organic growth of 35% per year and a gross margin of 78%. The annual gross customer churn stands at 8% (volume) and the net churn at 3% (given the growth of existing accounts), consistent with B2B mid-market benchmarks. The founder, backed by a minority private equity fund, is considering a sale of control to a strategic American acquirer and mandates an independent expert.

The valuation deploys two converging approaches. The approach by comparable transaction multiples on the European B2B SaaS mid-market segment 2024-2025 produces a range of 5 to 7 times ARR, i.e. 60 to 84 MCHF, with a median at 6 times ARR (72 MCHF). The DCF approach over seven years with terminal value, a WACC of 11.5% and a perpetual growth rate of 3% produces, without additional technological attrition, a net present value of 72 MCHF, consistent with the median of the multiples.

The independent expert judges this first valuation incomplete, because it ignores the additional technological obsolescence linked to the ongoing migration of the supply chain market toward architectures integrating generative artificial intelligence and real-time prescriptive optimisation, technologies absent from the publisher's current platform. This sectoral migration, observable since 2023-2024 among the American leaders of the segment, projects an additional technological attrition rate of 4% per year on the flows from year 3, modelling the growing competitive pressure. The economic valuation of SaaS in the age of AI now treats this dimension as central.

The DCF reworked with a technological attrition rate of 4% per year in years 3-7 (in addition to the customer churn of 3% already captured in the revenue assumptions) produces a net present value of 58 MCHF. The expert ultimately retains a central valuation of 60 MCHF, at the lower bound of the multiples range, justified by the obsolescence pressure linked to AI, and recommends that the founder accelerate the integration of a generative-AI module into the product roadmap to defend this bound rather than a sharper discount.

The disposal closes six months later at 62 MCHF in enterprise value. The 12 MCHF gap between the initial gross valuation (72 MCHF) and the effective transaction price (62 MCHF) corresponds very precisely to the impact of the technological attrition rate adopted, which validates ex post the relevance of the parameter in the valuation. The founder, who had initially contested the discount, acknowledges in the post-closing debriefing that the explicit accounting for technological obsolescence avoided a disappointment at the moment the offers were received and structured a rational rather than emotional negotiation.

The executive's perspective

The attrition rate is probably the most misunderstood parameter in the valuation of technology assets. Many experts ignore it out of methodological comfort, some apply it dogmatically without empirical calibration, others double it with a risk premium in the WACC without noticing. The professional practice codified by Pierre Breesé and Alain Kaiser in their reference work remains, twenty years after its first publication, the standard against which to measure the quality of a French-language IP valuation report.

What we observe on the franco-Swiss market for technology-asset valuation: post-acquisition PPAs that overvalue patents and developed technologies by 25% to 35%, annual impairment tests that fail to trigger when economic reality commands a material write-down, disposals of SaaS publishers where the seller discovers, at the moment the offers are received, that its target valuation ignored the obsolescence pressure linked to generative artificial intelligence, and intragroup operations contested by the tax authority for want of sufficient documentation on the duration of future benefits.

Our conviction is that integrating a documented attrition rate, empirically calibrated and properly articulated with the discount rate, radically transforms the quality of a technology-asset valuation. It is not only a question of methodological precision: it is a question of defensibility before the auditor, the tax authority and the judge in the event of dispute. And it is also a question of rational structuring of the M&A negotiation for intangible assets whose real economic value is too often decorrelated from their apparent legal life.

Aristide Ruot, Ph.D — Founder & CEO, Hectelion SA

FAQ: the 10 essential questions on the technology attrition rate

Introduction: what to keep in mind before the questions

The attrition rate systematically raises the same questions among tech executives, CFOs of SaaS publishers, R&D heads of biotechs and statutory auditors facing a PPA or an impairment test. This FAQ gathers the ten most frequent questions, ranked from the concept (the difference with the WACC) to the operational framework (calibration, standards, Hectelion's scope of intervention). The answers below summarise the state of French and Swiss practice as at 2026 and constitute a starting point — each situation calls for a specific analysis.

Q1: What is the attrition rate of a technology asset?

The attrition rate is the annual percentage decline in the economic value or the cash flows generated by a technology intangible asset (patent, software, SaaS customer base, technology brand), under the effect of technical obsolescence, competition by substitution, customer churn or contractual erosion. It is applied upstream of the discount rate in a DCF model and reflects the non-linearity of the real economic decline.

Q2: What is the difference between attrition rate and technological obsolescence?

Technological obsolescence is the underlying economic phenomenon — the loss of competitive advantage of an asset against more recent or more performant technologies. The attrition rate is the quantitative translation of this obsolescence in a financial model: an annual percentage applied to the flows to model the dynamic of decline. Obsolescence is a concept; the attrition rate is a model parameter.

Q3: Why is the discount rate (WACC) not enough to capture obsolescence?

The WACC reflects the general cost of capital and the market risk premium. It aggregates all risks (financial, operational, sectoral) into a single rate applied uniformly to all flows. The attrition rate, by contrast, isolates the specific risk of technological obsolescence and allows it to be modulated over time (variable by phase) and by asset class (differentiated by technology). Doubling the two parameters for the same risk is a frequent methodological error, but using them separately with distinct roles is the correct practice codified by the IVSC.

Q4: How do you calibrate an attrition rate for a patent?

The calibration relies on four converging sources: historical sales curves of comparable molecules or technologies after expiry or substitution, patent citation analyses measuring the declining citation rate as a proxy for the erosion of advantage, benchmarks published by the specialised IP firms (IP TRUST, BV4, Aon, Houlihan Lokey) and sectoral studies (EvaluatePharma for pharma, Gartner/IDC for tech). The rate adopted is generally variable by phase, with an acceleration after the commercial peak. Our patent valuation methodology details these approaches.

Q5: How do you calibrate an attrition rate for a SaaS?

For a SaaS publisher, the calibration distinguishes the customer churn (measured on the ARR or on the number of accounts) and the additional technological attrition linked to the obsolescence of the platform (architecture, technical stack, business model). The customer churn is calibrated on the cohort-retention curves specific to the segment (SMB, mid-market, enterprise) and on the public benchmarks (1% to 5% per month for SMB, 0.5% to 2% for mid-market, < 1% for enterprise). The additional technological attrition is calibrated on the prospective competitive analysis and typically represents an additional 2% to 5% per year on segments subject to sectoral rupture (generative AI in 2024-2026, cloud-native migration, etc.).

Q6: Does the attrition rate apply to all intangible assets?

No. The attrition rate is relevant for technology assets subject to obsolescence (patents, software, technical databases, developed technologies, SaaS contracts). It is much less relevant for pure non-technological brands (Coca-Cola, Hermès, LVMH), for legal intangible assets with stable duration (concessions, localised goodwill of a business) or for unidentified residual goodwill. For the latter, valuation relies more on indefinite useful lives (tested annually by impairment) than on an explicit attrition rate.

Q7: Which accounting standard governs the attrition rate?

IAS 38 (intangible assets) requires the entity to assess the finite or indefinite useful life of an intangible asset by accounting for all relevant factors, in particular technical, technological, commercial or other obsolescence (IAS 38.88-90). The IVS 210 framework of the International Valuation Standards Council explicitly recommends accounting for an attrition factor when the value of an intangible asset is derived from future flows. Swiss GAAP FER 27 follows an analogous logic. The attrition rate is the quantitative instrument that formalises these normative requirements.

Q8: Should an attrition rate be integrated in a post-acquisition PPA?

Yes, systematically for the technology assets identified in a PPA (developed technologies, patents, recurring customer base, fixed-term contracts). The attrition rate conditions the finite useful life adopted and therefore the amortisation schedule, which itself conditions the annual amortisation charge in the post-acquisition income statement. A PPA without a documented attrition rate is regularly contested by Big Four statutory auditors at first review.

Q9: Which rate to adopt in the absence of available historical data?

In the absence of historical data specific to the asset, the expert relies on four cumulative strategies: analogy with comparable assets from a documented neighbouring segment, published sectoral benchmarks (IP firms, IDC/Gartner reports), opinions of external technical experts (consultants specialised in the segment), and a broadened sensitivity analysis (testing over a wide range, for example 5% to 15%, with retention of the defensible central scenario). The documentation of the methodological choices is more important than the absolute precision of the rate adopted.

Q10: Does Hectelion work on technology-asset valuations?

Yes. Hectelion produces technology-asset valuations for SaaS publishers, biotechs, medtechs, deep tech scale-ups and franco-Swiss industrial groups, aligned with the IVSC standards, the codified Breesé-Kaiser practice and the IFRS / FER requirements. Our practice covers post-acquisition PPA engagements, annual impairment, intragroup transfer pricing on intellectual property, pre-disposal valuation and fairness opinion on IP assets, for unit assets whose value is between 2 and 500 MCHF. Let's talk for 30 minutes in confidence to frame your valuation project.

Conclusion: integrating attrition to defend the real economic value

The technology attrition rate has established itself as a central parameter in the valuation of intangible assets subject to obsolescence — patents, software, developed technologies, SaaS contracts, recurring customer bases. Codified by Pierre Breesé and Alain Kaiser in their French-language reference work, aligned with the requirements of IAS 38 and the IVS 210 framework, it provides the quantitative translation of the real economic erosion of a technology asset beyond its apparent legal life.

For the executives of SaaS publishers, biotechs, medtechs and deep tech scale-ups in France and Switzerland facing a PPA, an impairment test, an intragroup operation or a disposal, the integration of a documented attrition rate represents a modest methodological investment relative to the tax, accounting and economic risk it covers. The choice of an independent expert mastering the Breesé-Kaiser doctrine and the IVSC standards, experienced in the technology segment of the asset, and able to defend its parameters publicly, directly conditions the evidentiary value of the report. Hectelion SA works on this scope for technology assets in France and Switzerland, with a practice aligned with the IVSC standards and the market practice of the specialised IP firms, and economic independence from traditional financial intermediaries.

Summary of the article

The technology attrition rate is the annual percentage decline in the economic value of an intangible asset subject to obsolescence — patent, software, developed technology, SaaS contract, recurring customer base. Conceptualised in France by Pierre Breesé and Alain Kaiser in L'évaluation financière des droits de propriété intellectuelle (Gualino, 2010), it has established itself as a standard of professional practice in the valuation of intangible assets in the French language.

Its purpose is multiple: to restore consistency between the legal life and the economic life of a technology asset, to incorporate the sectoral asymmetry of obsolescence, to secure the tax defensibility of valuations in intragroup operations, to align the valuation with the IFRS / FER requirements on useful life, and to rationally structure the M&A negotiation on SaaS publishers, biotechs and IP portfolios. The methodology relies on six steps: characterise the asset, identify the obsolescence factors, empirically calibrate the rate, structure its application in the DCF model, conduct sensitivity tests and document consistency with the other financial parameters.

The normative framework includes IAS 38 (useful life accounting for obsolescence), IVS 210 (attrition factor for intangible-asset flows) and the French and Swiss tax doctrine on transfer pricing on intellectual property, in line with the OECD principles. The frequent mistakes to avoid are the confusion between legal life and economic life, double counting with the WACC, the application of a constant rate over the entire horizon, the omission of incremental maintenance innovation and the neglect of sectoral benchmarks.

The choice of the expert depends on three criteria: demonstrated technology sector expertise, multi-referential methodological mastery, and the ability to defend the conclusions before auditors and the tax authority. Hectelion SA works on this scope for franco-Swiss technology assets whose unit value is between 2 and 500 MCHF, with a practice aligned with the Breesé-Kaiser doctrine, the IVSC standards and the IFRS / FER requirements.

Sources

• Pierre Breesé and Alain Kaiser, L'évaluation financière des droits de propriété intellectuelle — Brevets et Actifs technologiques, Gualino, ISBN 9782297060448 — gualino.fr
• IFRS Foundation, IAS 38 Intangible Assets, paragraphs 88 to 96 on useful life and obsolescence — ifrs.org
• International Valuation Standards Council, IVS 210 Intangible Assets, 2024 edition — ivsc.org
• OECD, Transfer Pricing Guidelines for Multinational Enterprises and Tax Administrations, chapter VI on intangibles — oecd.org
• Bulletin Officiel des Finances Publiques (BOFiP), French tax doctrine on the valuation of intangible assets — bofip.impots.gouv.fr
• Swiss Federal Tax Administration (ESTV), Swiss practice on transfer pricing on intellectual property — estv.admin.ch
• IP TRUST, Pierre Breesé's firm, methodology for the financial valuation of IP rights and know-how — iptrust.fr
• Valuation of patents: difficulties and research avenues, reference academic article — researchgate.net
• WIPO (World Intellectual Property Organization), Patent Valuation Manual — wipo.int
• Aon Intellectual Property Solutions, Patent and IP Valuation Benchmarks — annual report
• Gartner and IDC, sectoral reports on SaaS, cloud infrastructure and generative-AI technology cycles — 2024-2026
• Hectelion SA — Internal observation, franco-Swiss technology-asset valuation market, 2025-2026

Author

Aristide Ruot, Ph.D.
Founder | Chief Executive Officer, Hectelion SA