Sum-of-the-Parts Valuation Method: The Logic Behind Valuing Diversified Holding Companies

The Hong Kong Exchanges and Clearing Limited (HKEX) reported 72 new listings in 2024, raising a combined HKD 87.5 billion, a 23% increase year-on-year from HKD 71.0 billion in 2023. This recovery, driven by a string of large-scale Main Board debuts from diversified conglomerates and state-owned enterprises, has refocused investor attention on a persistent valuation anomaly: the holding company discount. For CFOs and financial advisors structuring these entities, the sum-of-the-parts (SOTP) valuation method has moved from a theoretical exercise to a critical tool for navigating the HKEX Listing Rules, particularly Main Board Chapter 8 on eligibility and Chapter 19 on equity securities. The SFC’s 2024-25 enforcement priorities, which explicitly target misleading financial disclosures in complex corporate structures, further underscore the need for rigorous, defensible valuations. This article examines the mechanics, regulatory context, and practical execution of SOTP valuation for diversified holding companies listed or seeking listing in Hong Kong, providing a framework grounded in market data and primary source requirements.

The Structural Logic of SOTP in a Hong Kong Context

Why the Holding Company Discount Persists

The holding company discount — the gap between a diversified conglomerate’s market capitalisation and the sum of its individually valued subsidiaries — typically ranges from 15% to 30% for Hong Kong-listed entities, according to a 2023 study by the CFA Institute Research Foundation. This discount arises from structural inefficiencies: double taxation at the parent and subsidiary levels, management overheads, and the lack of a pure-play investment thesis for each business segment. For a company like CK Hutchison Holdings Limited, which reported consolidated revenue of HKD 275.6 billion for the year ended 31 December 2024, its five core business segments — ports, retail, infrastructure, telecommunications, and energy — trade at an implied discount of approximately 18% relative to their listed peers, based on Bloomberg consensus data as of Q1 2025.

The SOTP method addresses this by valuing each business unit independently, applying segment-specific multiples, and then deducting net debt, minority interests, and holding company costs. Under HKEX Listing Rule 19.60A, a listed issuer must disclose the basis of valuation for any material acquisition or disposal, which in practice compels the use of SOTP for conglomerates with multiple, non-integrated segments. The SFC’s Code on Takeovers and Mergers (the Takeovers Code) further requires that any valuation used in a general offer must be fair and reasonable, with a clear methodology, making SOTP the default standard for complex group structures.

Segment Identification and Revenue Attribution

The first step in constructing an SOTP model is segment identification, governed by HKEX Listing Rule 14.04(1), which defines “business” in the context of notifiable transactions. Each segment must be a distinct, revenue-generating unit with its own management, assets, and regulatory profile. For example, a holding company with a property development arm, a logistics division, and a financial services unit cannot simply aggregate these under a single “other” category. The HKEX’s 2023 Guidance Letter HKEX-GL108-23 explicitly states that issuers must provide segmental information in compliance with Hong Kong Financial Reporting Standard (HKFRS) 8, which requires disclosure of operating segments based on internal management reporting.

Revenue attribution must be precise. For a conglomerate like NWS Holdings Limited, which reported HKD 27.8 billion in revenue for FY2024, the breakdown is as follows: roads (HKD 8.2 billion), construction (HKD 12.1 billion), insurance (HKD 4.5 billion), and others (HKD 3.0 billion). Each segment requires a separate valuation methodology — a discounted cash flow (DCF) for the construction business given its long-term contracts, a comparable company analysis (CCA) for the insurance arm against HK-listed insurers, and a net asset value (NAV) approach for the roads portfolio, which holds concession assets. The SOTP model then applies a segment-specific cost of equity, derived from the capital asset pricing model (CAPM) using the Hong Kong risk-free rate (the 10-year HKD government bond yield, which stood at 3.45% as of March 2025) and an equity risk premium of 6.5%, per Duff & Phelps’ 2024 Hong Kong Valuation Handbook.

Methodological Approaches and Multiples Selection

The Comparable Company Analysis (CCA) Framework

The CCA is the most common methodology for SOTP, relying on a set of publicly traded pure-play peers for each segment. For a Hong Kong-listed conglomerate, the selection of comparables must consider both the HKEX Main Board and the GEM, as well as offshore exchanges such as the Singapore Exchange (SGX) and the Shanghai Stock Exchange (SSE), where comparable businesses may trade at different multiples due to market structure. The SFC’s 2024 Consultation Paper on the Regulation of Sponsors (SFC CP-2024-05) emphasises that any peer selection must be justified, with a clear explanation of why each comparable was chosen and why others were excluded.

Key multiples include:

• Enterprise Value to EBITDA (EV/EBITDA): Preferred for capital-intensive segments like infrastructure and telecommunications. The median EV/EBITDA for HK-listed infrastructure companies was 9.8x in 2024, per Bloomberg data, while telecommunications traded at 7.2x.
• Price to Earnings (P/E): Used for financial services and consumer-oriented segments. The Hang Seng Finance Index had a trailing P/E of 10.5x as of 31 December 2024.
• Price to Book (P/B): Applied to asset-heavy segments like property development. The Hang Seng Properties Index traded at a P/B of 0.68x in Q1 2025.

For example, valuing the property segment of a conglomerate using the P/B approach requires adjusting the book value for fair value gains on investment properties under HKFRS 16. The SOTP model must then apply a liquidity discount of 10-15% for the parent’s stake, as per the 2023 HKMA Research Paper on Conglomerate Discounts, which found that illiquid stakes in unlisted subsidiaries trade at a 12% median discount to NAV.

Discounted Cash Flow (DCF) for Long-Duration Assets

For segments with predictable, long-term cash flows — such as toll roads, utilities, or concession-based operations — a DCF model is appropriate. The SOTP approach must align with HKEX Listing Rule 19.60A, which requires that any valuation used in a notifiable transaction be based on “reasonable assumptions” and include a sensitivity analysis. The DCF model for a road concession, for instance, would project free cash flows over the remaining concession period (e.g., 15 years), apply a terminal value using the Gordon Growth Model with a perpetual growth rate of 2.5% (in line with Hong Kong’s long-term GDP growth forecast of 2.3% per the HKMA’s 2024 Monetary and Financial Stability Report), and discount at a weighted average cost of capital (WACC) of 7.8%.

The SFC’s 2023 Enforcement Report cited a case where a sponsor’s DCF model for a toll road asset failed to account for regulatory changes in toll rates, resulting in a 40% overvaluation. To avoid such pitfalls, the SOTP model must incorporate explicit assumptions about regulatory caps, concession renewal risks, and foreign exchange exposure for cross-border assets, particularly those in Mainland China where the HKMA’s 2024 circular on cross-border renminbi settlement (HKMA B9/1C) requires disclosure of currency risk in valuation reports.

Regulatory and Disclosure Requirements

HKEX Listing Rules on Notifiable Transactions

When a diversified holding company undertakes a material acquisition or disposal, the SOTP valuation becomes a regulatory requirement. HKEX Listing Rule 14.06B specifies that the “assets test,” “profits test,” “revenue test,” and “consideration test” must be applied to each segment individually if the transaction relates to a specific business unit. For example, if a conglomerate sells its logistics division, the consideration test — comparing the transaction value to the issuer’s market capitalisation — must be calculated using the segment’s standalone financials, not the consolidated group. The SOTP model provides the basis for this segmentation, allowing the issuer to determine whether the transaction crosses the 5%, 25%, or 100% thresholds for disclosure, shareholder approval, or a circular.

The HKEX’s 2024 Guidance Letter HKEX-GL124-24 further clarifies that for “very substantial acquisitions” (Rule 14.06(5)), the issuer must include a valuation report prepared by an independent financial adviser (IFA). The IFA’s report must explicitly state the SOTP methodology, the multiples used, and the rationale for any discounts or premiums applied. Failure to do so can result in a suspension of trading, as seen in the 2023 case of a Main Board issuer whose shares were halted for 14 trading days pending a revised valuation circular.

SFC Code on Takeovers and Mergers

For general offers or privatisations involving a diversified holding company, the SFC’s Takeovers Code Rule 11.1 requires that the offer document include a valuation of the target’s assets if the offer is for a company with significant asset backing. The SOTP method is the preferred approach because it isolates the value of each subsidiary, enabling the IFA to opine on whether the offer is “fair and reasonable.” The SFC’s 2024 Annual Report noted that in the 12 months to 31 March 2024, 8 out of 15 contested offers involved conglomerates where the SOTP valuation was contested by minority shareholders, leading to revised offer terms in 3 cases.

The Takeovers Code also mandates that any valuation must be updated within 3 months of the offer date if market conditions change materially. For a conglomerate with listed subsidiaries, this means the SOTP model must be recalibrated daily based on the subsidiaries’ share prices, which are observable on the HKEX. The discount to NAV must be disclosed explicitly, with a sensitivity analysis showing how a 10% change in the discount rate or a 5% change in the subsidiaries’ market prices affects the SOTP value.

Practical Challenges and Mitigation Strategies

Cross-Border Subsidiaries and Jurisdictional Complexity

A significant challenge in SOTP valuation is the treatment of subsidiaries incorporated in different jurisdictions — BVI, Cayman, Bermuda, or the PRC. Each jurisdiction has distinct tax regimes, legal frameworks, and disclosure requirements. For a Hong Kong-listed holding company with a PRC subsidiary structured as a variable interest entity (VIE), the SOTP model must account for the VIE’s contractual arrangements, which the HKEX’s 2024 VIE Guidance (HKEX-GL126-24) requires to be disclosed in full, including the risk of the PRC government invalidating the VIE structure. The valuation of such a subsidiary typically applies a 20-30% discount to its operating metrics to reflect the structural risk, based on the 2024 MSCI China VIE Risk Index.

For a BVI-incorporated subsidiary, the SOTP model must consider the BVI Business Companies Act (2004) and its implications for dividend repatriation, which affects the parent’s cash flow. The HKMA’s 2024 circular on offshore financial centres (HKMA B10/2C) requires banks to conduct enhanced due diligence on BVI entities, and this risk is priced into the cost of equity for such subsidiaries, adding 50-75 bps to the WACC.

Minority Interests and Consolidation Adjustments

Under HKFRS 10, a parent must consolidate subsidiaries where it controls more than 50% of the voting rights. However, for SOTP valuation, the parent’s stake in each subsidiary is valued at its proportional share of the subsidiary’s equity value, with the minority interest deducted at the group level. This is straightforward for wholly owned subsidiaries but complex for partially owned ones. For example, if a conglomerate holds a 60% stake in a listed subsidiary trading at HKD 10.0 billion, the SOTP model attributes HKD 6.0 billion to the parent, but the minority interest of HKD 4.0 billion must be deducted from the group’s total SOTP value.

The HKEX’s 2024 Guidance Letter HKEX-GL127-24 on minority interest disclosures requires that the SOTP model explicitly state the minority interest deduction and provide a reconciliation to the consolidated financial statements. This is particularly important for conglomerates like Swire Pacific Limited, which as of FY2024 held a 82% stake in Swire Properties Limited (market cap HKD 55.0 billion) and a 40% stake in Cathay Pacific Airways Limited (market cap HKD 38.0 billion). The SOTP model must deduct the 18% minority interest in Swire Properties (HKD 9.9 billion) and the 60% minority interest in Cathay Pacific (HKD 22.8 billion), while also accounting for the parent’s holding company costs, which Swire Pacific reported as HKD 1.2 billion in FY2024.

Actionable Takeaways

1. For diversified holding companies planning a HKEX listing or a notifiable transaction, the SOTP valuation must be prepared in compliance with HKEX Listing Rule 14.06B and HKFRS 8, with each segment valued using a methodology appropriate to its cash flow profile and regulatory environment.
2. When selecting comparable companies for the CCA, the peer group must be justified against the SFC’s 2024 Consultation Paper on Sponsors, excluding any comparables that do not share the same business model, geographic exposure, or regulatory regime.
3. The discount to NAV must be disclosed explicitly, with a sensitivity analysis showing the impact of a 10% change in the discount rate and a 5% change in subsidiaries’ market prices, as required by the SFC’s Takeovers Code Rule 11.1.
4. For subsidiaries in BVI, Cayman, or PRC VIE structures, the SOTP model must apply a jurisdictional risk premium of 50-75 bps to the WACC, supported by the HKMA’s 2024 circular on offshore financial centres.
5. The minority interest deduction must be reconciled to the consolidated financial statements under HKFRS 10, with the SOTP model providing a line-by-line breakdown of the parent’s proportional stake in each subsidiary and the corresponding minority interest.