MELROSE INDUSTRIES PLC (MRO) — Investment Research Note

Executive summary

Melrose is a UK-listed "Super-Tier 1" aerospace group with two divisions — Engines (industry-leading margins ~34% with a diversified portfolio of 19 risk-and-revenue-sharing partnerships) and Airframes (design-to-build structures at ~6-7% margins, targeted at low-teens by 2029). Since demerging Dowlais (automotive) in April 2023, Melrose has delivered a sustained upgrade in operating margins (Aerospace adjusted operating margin rose from ~6% in 2022 to 18.0% in 2025 and 18.5% in H1 2026), driven by aftermarket mix, OEM ramp-up, and restructuring benefits 2025 final results; 2026-07-31 half-year. The dominant valuation issue today is the Garden Grove California chemical incident of May 2026 — an event that has paused the £175m buyback, triggered 30+ civil lawsuits and regulator inquiries, and creates uncertain but potentially material tail-liability that has driven the share price from 681p to 462p 2026-07-31 half-year.

Fair value estimate

Fair value range: 520p – 640p per share (implied market cap £6,510m – £8,010m)

Methodology — blended multiple approach on 2026 guidance, cross-checked with medium-term cash flow target:

• Forward P/E: 2026 guidance implies adjusted diluted EPS of ~36-38p (adjusted PBT of ~£585m on tax rate 21%, ~1,246m shares). Applying a 15–17x P/E (reasonable for a design-led aerospace Super-Tier 1 with 19% margins, vs. Safran ~22x, Rolls-Royce ~25x, BAE ~18x) gives 540–650p.
• EV/EBITDA: LTM adjusted EBITDA of £825m 2026-07-31 half-year. Applying 10–12x (mid-cycle aerospace multiple) gives EV of £8,250–9,900m; less £1,530m net debt = market cap £6,720–8,370m = 540–670p.
• Medium-term FCF anchor: 2029 target is £600m FCF after interest and tax. Discounted at 10% for three years and applying a 20x multiple = c.£9bn value, or ~720p/share (upside scenario if targets are met).

I have haircut the range by ~10% versus these approaches to account for Garden Grove tail liability (an incremental £100-300m of legal, regulatory and compensation exposure is plausible; insurance recovery is under review).

Mid-point 580p implies market cap of £7,260m vs. current £5,860m — absolute upside of ~26% on the mid, range of +13% to +39%.

Sector context

Confirmed classification: Industrial Goods and Services / Aerospace & Defense. This is a higher-quality-than-typical name for the sector — Engines margins in the 30%s are aerospace-elite, comparable to TransDigm's aftermarket business and above Safran's LEAP engine RRSP economics. Airframes is a more commoditised structures business but has been repositioned to design-to-build content. Balance sheet leverage of 1.8x is in line with peers. Listed peers: Rolls-Royce Holdings (engines), Safran (engines/nacelles), BAE Systems (defence), and privately-held (post-Parker acquisition) Meggitt.

Investment thesis

• Engines is an outstanding franchise with long-tail cash flows. 19 RRSP partnerships (GTF, LEAP, CFM56, V2500, GEnx, XWB, etc.) generate 33.8% margins and are entering their high-cash aftermarket phase, with c.£22bn of expected future RRSP net cash flows over the coming decades. GTF programmes turn cash-positive in 2028 2025 final results; 2026-07-31 half-year.
• Structural tailwinds from record OEM backlog and defence spending. Airbus/Boeing narrow- and wide-body backlogs are 9 years and Airbus targets 70-75/month A320 production by end-2027. NATO members are moving to 3.5% GDP defence spend by 2035, driving F-35, Gripen, missile and uncrewed programmes where MRO has embedded content 2025 final results; 2026-07-31 half-year.
• Valuation reflects Garden Grove worst-case, giving room for re-rating. Shares are down 32% from the 52-week high; at 12.5x forward P/E the market appears to be discounting a material adverse outcome. If Garden Grove is contained to £150–250m of exceptional cost (management's guided £25-30m in H2 plus ongoing lawsuits), the stock re-rates towards 600p+ 2026-07-31 half-year.

Key risks

• Garden Grove legal/regulatory tail. 30+ civil lawsuits, multiple regulator inquiries, a potential compensation programme for local residents/businesses, and insurance under review. Management explicitly could not reliably quantify the impact at H1 2026 — this could easily be £150-400m of net cost including litigation, remediation and lost production 2026-07-31 half-year.
• Cyclical civil aerospace exposure. 71% of H1 2026 revenue was civil; a global downturn or oil-price shock (the mid-2026 US–Iran conflict already knocked 3% off Q2 flight hours) would compress narrowbody OE builds and delay the aftermarket monetisation curve 2026-07-31 half-year.
• Statutory-to-adjusted gap and earnings quality. Adjusted operating profit of £347m in H1 2026 vs. statutory £154m — a £193m gap dominated by £124m acquired-intangible amortisation and £56m derivative fair-value swings 2026-07-31 half-year. Adjusted EPS growth of 22% (17.7p) contrasts with statutory diluted EPS falling from 22.2p to 6.0p. Reasonable investors could apply a valuation discount for this complexity.

Operating leverage

Melrose has meaningful operating leverage, particularly in Engines. The Engines cost base is dominated by fixed R&D, specialised manufacturing capacity (Trollhättan, Norway, San Diego, Newington CT), and long-term RRSP contract obligations, with variable cost related principally to raw materials and specialised alloys. The proof: in H1 2026 Engines revenue grew 19% while adjusted operating profit grew 21% and margin rose 40bps to 33.8% — indicating incremental operating profit margins on new revenue of ~35-40% 2026-07-31 half-year. Variable consideration from RRSP contracts (£206m in H1 2026 vs £182m prior) is high-margin annuity revenue as customer engines are delivered. Airframes has more modest leverage — H1 2026 revenue up 4% but operating profit down 1% due to Garden Grove; on an underlying basis (ex Garden Grove) operating margin expanded from 6.7% to 7.2%, suggesting drop-through of ~30-40% on incremental revenue as fixed sites (Netherlands, Filton, Mexico) absorb higher volumes 2026-07-31 half-year. If Group revenue exceeds the 2026 guidance mid-point of £3.85bn by 10-20%, incremental operating profit could plausibly be £150-260m, or 20-35% above the 2026 op-profit guidance mid — meaningful leverage, though not the multiples-of-profit uplift you'd see in pure software.

Value-trap signals

None identified as structural. Garden Grove is an idiosyncratic incident, not a business-model concern. Order backlog is at record levels, aftermarket dynamics are strongly positive, and management has been consistently beating its own guidance. The one soft signal is the persistent gap between adjusted and statutory earnings driven by acquisition amortisation and derivative volatility — worth watching, but not a flag by itself.

Earnings vs. expectations

• 2023 full year: guided £350m adjusted operating profit (pre-PLC costs) initially; upgraded twice; delivered £420m — beat by ~20%.
• 2024 full year: initial guidance £560m midpoint; delivered £566m Aerospace operating profit (pre-PLC); in line/small beat.
• 2025 full year: guidance £620–650m post-PLC; delivered £647m — top of range.
• H1 2026: guidance reiterated at AGM (Apr) and confirmed at H1 (Jul) despite Garden Grove; H1 operating profit +16% year-on-year — in line with expectations ex-Garden Grove.

Pattern: consistent modest beats and upward guidance revisions since the demerger, with no profit warnings. Garden Grove is the first material negative surprise.

Conviction

Conviction: 3 (moderate).

Anchoring the call: (i) disclosure quality is high and consistent, with detailed segment-level guidance and adjusted-to-statutory reconciliations; (ii) 2026 guidance and 2029 medium-term targets are well-articulated and management has a track record of delivery; (iii) multiple valuation approaches converge on a similar range.

Limiting the call: (i) Garden Grove financial impact is explicitly not quantifiable at the H1 2026 reporting date — the range of outcomes is wide; (ii) large gap between adjusted and statutory earnings introduces analytical noise.