AIM’s biggest companies and how they performed in 2025

Despite the takeovers and moves to the Main Market of some of AIM’s larger companies, there are currently seven AIM companies valued at more than £1 billion, up from six last year. Four of those companies are the same.

Two of last year’s contingent have moved to the Main Market and the other plans to next year. More of AIM’s biggest companies are also planning or thinking about the move.

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AIM’s biggest companies

Source: ShareScope at 18 December 2025. Past performance is not a guide to future performance.

The only one of last year’s six companies where the share price has risen is uranium investor Yellow Cake Ordinary Shares (LSE:YCA) with a gain of 8.8%

The outlook for demand for uranium remains strong with expansion of global nuclear capacity, although the price can be volatile. Uranium investor Yellow Cake raised £126 million ($169 million) at 564p/share at the end of September. That was more than the original amount sought and enabled the full exercise of the uranium purchase option under the framework with Kazatomprom. There is also cash to make other opportunistic uranium purchases.

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In the six months to September 2025, there were gains on uranium holdings of $380.5 million. Net assets were $1.96 billion, including cash of $184.2 million prior to exercising the purchase option. The market capitalisation is £1.3 billion.

Airline and tour operator Jet2 Ordinary Shares (LSE:JET2) continues to grow market share. There is uncertainty over demand and pricing, though, and more passengers are booking flights only. Last year’s margin was unusually high, and it is likely to fall back this year.

Full-year revenues are expected to rise from £7.17 billion to £7.58 billion, while pre-tax profit is forecast to fall from £577.7 million to £542.2 million.

Longer-term benefits will come from Jet2 moving into Gatwick in March 2026. There are 15 million potential customers within one hour of Gatwick, which will be the 14th airport that Jet2 will fly from.

There will be initial pre-start-up costs in 2025-26 and there could be a loss of up to £60 million in 2026-27 as business is built up. There should be a four- to five-year payback from the investment. The share price declined 12.6% to £13.83, valuing the company at £2.6 billion.

Cancer and immunological treatments developer HUTCHMED (China) Ltd (LSE:HCM) has received approval for follicular lymphoma treatment Tazverik. It also launched Fruquintinib in more countries and sales rose by 22%, despite a decline in the US. There was progress with other treatments.

Savolitinib could become the second global asset next year. Partner AstraZeneca expects phase III SAFFRON non-small cell lung cancer study topline data in the first half of 2026. This is a treatment incorporating savolitinib. Over the coming year there are regulatory decisions expected on some treatments and new product launches.

The share price declined 14.8% to 200p, valuing the pharma company at £1.72 billion. It is expected to have cash of $1.39 billion at the end of 2025.

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Litigation funder Burford Capital Ltd (LSE:BUR) is still on course to double in size by 2030, according to management. However, it swung from profit to loss in the third quarter of 2025, although it remains profitable in the nine-month period.

Burford Capital is a business where income and valuations can vary significantly from quarter to quarter. Large cases can have a big influence on value. The share price has fallen by one-third to 684.75p, valuing the company at £1.49 billion.   

Jet2 is moving into Gatwick in March 2026. There are 15 million potential customers within one hour of the airport.

Newcomers

Two of the three new £1 billion-plus companies were involved in reverse transactions. Greatland Resources Ltd (LSE:GGP) has taken over from Jet2 as the largest company on AIM with a market capitalisation of £3.25 billion. It redomiciled to Australia and acquired the 70% of the Havieron gold copper project in Australia that it did not own from Newmont Corporation. It also raised £30 million at 312p/share.

A feasibility study suggests that Havieron has a net present value calculated using a 5% discount rate (NPV5%) of £2.9 billion. The share price of the AIM transaction of the year winner has soared 277% this year to 479p and the upward trend is continuing.

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Cash shell Rosebank Industries Ordinary Shares (LSE:ROSE) secured its first acquisition during the year. It bought critical electrical distribution systems supplier Electrical Components International Inc (ECI) for $1.9 billion. 

A placing raised £1.15 billion at 300p/share, so it is no surprise that Rosebank is valued at £1.35 billion despite a 60.8% slump in the share price to 343p. There are plans to improve margins and cash generation and any indication of the success of this strategy could help the share price to recover.

Lime and building materials supplier SigmaRoc (LSE:SRC) completed its major acquisition of lime assets in 2024, and 2025 was when the cost savings and other benefits became significant. Net debt has hampered investor sentiment, but it is set to fall to £442 million at the end of 2025 and £333 million by the end of 2026, indicating the cash-generative nature of the business.

A 68.1% jump in the share price to 121p, values SigmaRoc at £1.33 billion. Yet, the prospective multiple is only 13, falling to 12 next year.  

Dropouts

Telecoms and network services provider Gamma Communications (LSE:GAMA) had already announced its intention to move to the Main Market in December 2024, and it completed the switch on 2 May 2025. 

Moving to the Main Market has not done anything for the share price, which has fallen by two-fifths this year and it is currently valued at well below £1 billion. That is despite entering the FTSE 250 index in June. There was a bump upwards in May, but the trend has been downwards all through the year.

Veterinary practices operator CVS Group is moving to the Main Market on 29 January.

Data and analytics information provider GlobalData (LSE:DATA) is the other company that dropped below £1 billion after the share price dropped by more than two-fifths. During the year there was also a tender offer of £60 million at 150p/share. There were bid approaches, but no firm offers were made.

Third-quarter revenues were 13.5% higher, partly thanks to growth in subscriptions. However, margins have weakened, and the 2025 pre-tax profit forecast was reduced to just over £100 million, up from £54.9 million in 2024.

GlobalData had planned to move to the Main Market in 2025, but this has been delayed and there will be news in January.

Subs bench

Veterinary practices operator CVS Group (LSE:CVSG) is potentially heading for £1 billion following a 48.3% share price recovery to £12.46, but it is moving to the Main Market on 29 January.

Mixer drinks supplier Fevertree Drinks (LSE:FEVR) was worth more than £1 billion two years ago but dropped out of the list last year. It is currently worth £956 million. In 2025, the share price has rebounded, and it was back above £1 billion earlier in the year, but it has dropped back again – still one-fifth ahead this year at 825p. There have been significant share buybacks.

The improvement was sparked by a strategic partnership with brewer Molson Coors, which acquired a 7.5% stake at 654.2p/share. The £71 million raised was used for share buybacks. The company’s mixer drinks will be sold through Molson Coors’ US distribution network and marketing will be ramped up. There will also be US production of mixer drinks.

Interim revenues were 2% lower at £172.2 million with growth in the US partly offsetting declines elsewhere. Pre-exceptional profit improved from £13.2 million to £15.3 million due to higher interest receipts. Cash nearly doubled to £130 million. The interim dividend is 2% higher at 5.97p/share. The prospective valuation multiple is 35.

Dublin-based international healthcare company Uniphar (LSE:UPR) performed strongly in 2025. The share price is more than four-fifths higher this year. The rise in the share price has been fuelled by organic growth rather than acquisitions. It is also a re-rating, because the prospective multiple is 15, showing how underrated it was previously. The forecast yield is more modest at 0.5%.

A €35 million (£30.6 million) share buyback launched in February may also have helped. This was completed in the first half of 2025. Most of the share price rise of 77.8% to 304p was in those six months, although it peaked at 353p in early September.

Uniphar publishes results in Euros. The change in the £/€ exchange rate will also have boosted earnings in pounds by around 5%. The market capitalisation is £795 million.

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Power cables and accessories supplier Volex (LSE:VLX) has been trading better than expected. Data centre and electric vehicles markets are particularly strong, and the international spread of manufacturing facilities has helped in adapting to tariffs. A new chairman will help Volex to expand in the US.

In the six months to September 2025, revenues increased from $518.2 million (£387 million) to $583.9 million, and the operating margin improved from 9.2% to 9.8%. Underlying pre-tax profit rose from $37.5 million to $48.5 million. This year, revenues should improve from $1.09 billion to $1.15 billion and pre-tax profit is forecast to rise from $88 million to $95 million.

The share price has risen 42% to 401.5p and the market capitalisation is £737 million.

*All share prices and performance data at 18 December 2025.

Andrew Hore is a freelance contributor and not a direct employee of interactive investor.