Caseware UK (AP4) 2024.0.164 2024.0.164 2025-12-312025-12-31683857113182494987935418890Amounts owed to group undertakings are non-interest bearing, unsecured and repayable on demand. Other creditors include £Nil (2024: £2,762,637) in respect of obligations relating to finance leases, payable in instalments and net of finance charges allocated to future periods. The contractual undiscounted lease payments due within one year are £Nil (2024: £4,091,162). The finance lease is secured to the assets to which it relates. In March 2024 a contract for software was renegotiated resulting in a remeasurement of the outstanding finance lease liability and related assets held under hire purchase agreements. This resulted in a decrease to the liability of £3,803,655 and a decrease to the asset of £2,142,387 for the year ending 31 December 2024. Other creditors include £Nil (2024: £7,124,841) in respect of obligations relating to finance leases, payable in instalments and net of finance charges allocated to future periods. The contractual undiscounted lease payments due after one year and before two years are £Nil (2024: £3,474,590). The contractual undiscounted lease payments due after two years and before five years are £Nil (2024: £5,491,193). The finance lease is secured to the assets to which it relates. Amounts owed to group undertakings are non-interest bearing, unsecured and repayable on demand. Other creditors include £Nil (2024: £2,762,637) in respect of obligations relating to finance leases, payable in instalments and net of finance charges allocated to future periods. The contractual undiscounted lease payments due within one year are £Nil (2024: £4,091,162). The finance lease is secured to the assets to which it relates. In March 2024 a contract for software was renegotiated resulting in a remeasurement of the outstanding finance lease liability and related assets held under hire purchase agreements. This resulted in a decrease to the liability of £3,803,655 and a decrease to the asset of £2,142,387 for the year ending 31 December 2024. During the year, amounts of £24,648,262 owed by the company to parent entity were formally released by the parent. 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Registered number: 04491953









AION SILICON LIMITED (FORMERLY SONDREL LIMITED)









ANNUAL REPORT AND FINANCIAL STATEMENTS

FOR THE YEAR ENDED 31 DECEMBER 2025

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
COMPANY INFORMATION


Directors
O W A Jones 
M S Julio 




Registered number
04491953



Registered office
33 Great Portland Street

London

W1W 8QG




Independent auditor
Grant Thornton UK LLP
Chartered Accountants & Statutory Auditor

1st Floor

One Valpy

20 Valpy Street

Reading

RG1 1AR





 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 

CONTENTS



Page
Strategic Report
 
1 - 4
Directors' Report
 
5 - 7
Independent Auditor's Report
 
8 - 13
Statement of Comprehensive Income
 
14
Balance Sheet
 
15
Statement of Changes in Equity
 
16
Notes to the Financial Statements
 
17 - 36


 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
STRATEGIC REPORT
FOR THE YEAR ENDED 31 DECEMBER 2025

The directors present the Strategic Report on the company for the year ended 31 December 2025.

Business review and future developments
 
Aion Silicon Limited (Formerly Sondrel Limited) is a UK founded and headquartered fabless semiconductor business providing turnkey services in the design and delivery of complex, high end 'application specific integrated circuits' ("ASICs") and 'system on chips' ("SoCs") for leading global technology brands the company’s capabilities are provided to customers seeking competitive advantage by including customised ASIC/SoC devices enabling differentiation of their end products when addressing fast growth technology megatrends. 

The company delivers complex ASIC/SoC designs on a consultancy and/or project basis for a wide range of leading multinational corporate customers. The high end complex ASICs/SoCs designed and supplied by the company to its customers and the company’s previous designs have been included in well-known products such as Apple iPhone, Sony PlayStation, Meta's Oculus Quest virtual reality headset, Samsung, Google and Sony smartphones, JVC prosumer camcorders and Tesla and Mercedes-Benz cars.
 
The company has transitioned its business model to include providing a full turnkey ASIC design and supply service for its customers. This includes contracting for the manufacture, testing and production of ASICs as well as previously offered design and production consulting. Although the testing, packaging, and other capital-intensive engineering functions necessary for production of an ASIC will continue to be outsourced to third parties, the company provides the product engineering and manages the complex manufacturing process by maintaining direct foundry partnerships with TSMC, Intel Foundry and GlobalFoundries.

Trading overview for 2025

Aion intends to continue strengthening its engineering capabilities and project delivery processes through the execution of the complex and advanced-node programmes currently underway, alongside targeted recruitment in key technical areas. These actions are expected to support the Company’s ability to deliver increasingly complex chip development programmes for global customers.

The Company also expects to continue investing in the promotion of Aion’s capabilities in North America as an architecture-led, end-to-end ASIC partner for customers bringing new chips to market, while building on its established position in Europe, the Middle East and Africa ("EMEA"). Management believes the increasing importance of artificial intelligence applications and chip sovereignty initiatives will continue to support demand in these markets.

Revenue in 2025 was £11.2million 
(2024: £7.9million), with a profit before tax of £9.7 million (2024: loss of £4.9 million). The increase in profit before tax this year was mainly driven by the increase in other administrative income of £9,887,478 (2024: £Nil). Further details of this are provided in note 5.

Rebranding

In 2025, the company completed a comprehensive rebrand from Sondrel Limited to Aion Silicon Limited, fundamentally repositioning the business for the next phase of its growth journey. The new name modernises the brand identity while explicitly signalling the company's strategic focus on artificial intelligence as a core growth market, with "Aion" reflecting a forward-looking vision and "Silicon" anchoring the company in the semiconductor design industry. This rebrand addresses establishing stronger recognition and market presence in the United States, where limited brand awareness had previously been identified as a growth constraint. The new identity positions Aion Silicon as a more US-centric player, reinforced by the company's expanded footprint including operations in Silicon Valley, membership in the Intel Foundry Accelerator Design Services Alliance, and active participation in North American industry events.

Page 1

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 

STRATEGIC REPORT (CONTINUED)
FOR THE YEAR ENDED 31 DECEMBER 2025

Office changes

During 2025, the company strategically rationalised its operational footprint to optimise cost efficiency and strengthen alignment with key stakeholders and markets. Following the end of the lease on the Theale, UK office, the company relocated its headquarters to London, enhancing proximity to partners and the capital's deep technology talent pool. Concurrently, the company opened a new 15-engineer design centre in Barcelona, Spain, positioned to capitalise on the European Union's chip sovereignty movement and support a cornerstone European customer engaged in advanced 18A/N4 datacentre chip development. This strategic reconfiguration reduces property costs, provides a centralised location allowing stronger access to the wider-UK semiconductor talent pool and establishes a vital engineering presence in Southern Europe to serve the growing demand for secure, regionally-anchored semiconductor design capabilities aligned with European Union strategic autonomy objectives.
 
Principal risks and uncertainties
 
The company faces various risks and uncertainties that have the potential to impact the company financially, operationally, strategically and reputationally. While it is not possible to identify or anticipate every risk, the principal risks and uncertainties faced by the company and the steps in place to mitigate these risks are described below. The board has overall responsibility for risk management and internal controls. 

Cyber security 

The company maintains a significant level of confidential customer data and relies on information technology systems to conduct its operations. Cyber-attacks can result from deliberate attacks or unintentional events and may include (but are not limited to) third parties gaining unauthorised access to the company's systems for the purpose of misappropriating intellectual property or confidential sensitive information, corrupting data, or causing operational disruption. 
If the company suffers a cyber-attack, whether by a third party or insider, resulting in a breach of confidentiality or a data security breach, it may incur significant costs, suffer reputational damage and loss of customer or investor confidence.
The company employs strict security protocols and policies to mitigate against any potential security breaches, including regular auditing of the company's security environment and controls under its accredited ISO 27001 and ISO 9001 standards and has recently gained Cyber Essentials Plus certification.

Project delivery 
Each customer project is unique, involving specific custom deliverables that the company has not previously developed. Projects are typically quoted on a partial fixed price and partial budgetary price based on an assessment of the work and IP required to deliver it to the customer schedule. It is possible that management may misjudge their ability to deliver at the estimated cost. Failure to do so could damage the current financials and long-term reputation.
Project management is focussed on delivering to the customer schedule. By careful management of engineer utilisation the business ensures sufficient resources are available to deliver the project to schedule. A close collaboration with the customer and IP vendors permits a clear scope of work to be agreed which together with a robust change management process ensures project risks are managed appropriately. Furthermore, complex projects are typically separated into phases and prices for later phases are typically quoted as budgetary based on a number of assumptions. This allows the scope of the project to evolve and develop through the project and pricing to be adjusted accordingly thereby reducing commercial risk.
 
Page 2

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 

STRATEGIC REPORT (CONTINUED)
FOR THE YEAR ENDED 31 DECEMBER 2025

Principal risks and uncertainties (continued)

Attraction and retention of talent

The company's ability to attract and retain key management and employees, including suitably qualified and experienced engineers, is critical to the company's continued development and innovation. Loss of key management or other key personnel, particularly to competitors, could have adverse consequences. 

The company may not be successful in identifying and engaging suitably qualified people or inducting them into the company, which may impact the performance of its business. In addition, the ability to attract and incentivise such individuals in the locations where the company operates requires proportionate budgeting and therefore can affect the capabilities of the company. Aion Silicon creates a positive and exciting workplace environment, through challenging engineering projects, training, regular engagement and feedback, rewards and values.
The company ensures that rewards correspond with performance and retention.

Liquidity risk

The company's ability to manage its cash and to meet its financial obligations as they fall due is essential to retaining key suppliers and employees. As a significant proportion of the company's cash receipts are dependent on achieving project milestones, cashflows may be disrupted if project delivery is delayed. 
The company monitors and manages its cash by preparing cashflow forecasts in its budgets and using sensitivity analysis.
Design Services contracts typically provide regular monthly payments, which provide cash receipts that are less likely to be disrupted. The company is deliberate in keeping a mix of Design Services and Turnkey projects to balance cash receipt risk. 
Contract management 
Silicon chip projects are tailored to individual customer requirements and the specification of each chip design may change significantly during the design process. Poor contract management may lead to project overruns, additional costs which are not recovered and reputational damage. 
The company operates a monthly Contract Monitoring review process to track, report and drive decisions to ensure robust commercial management of projects.
Project management collaborate closely with customers to communicate the impact of changes in specifications through a robust change management process to ensure customer expectations are met and project commercials are managed appropriately.

Innovation 
Silicon chip design is a rapidly developing field, in which we may struggle to compete if we fail to innovate. Aion Silicon has delivered designs at N3 (3 nanometres on TSMC), 2 nanometres (on Samsung) and 1.8 nanometres (18 angstrom on Intel Foundry) process nodes. This engineering capability enables Aion Silicon to benefit from megatrends driving the demand for system solutions with increasingly complex design geometries. Failure to stay at the cutting edge of the technology would neutralise its U.S.P. 
The company continually invests in its own IP development and has established and maintains relationships with key partners in the industry, which enable it to deliver compelling turnkey design and supply solutions.

 
Page 3

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 

STRATEGIC REPORT (CONTINUED)
FOR THE YEAR ENDED 31 DECEMBER 2025

Principal risks and uncertainties (continued)

Growth strategies and management 

The company's growth plans may place a significant strain on its management and operational, financial and personnel resources. Furthermore, the ability of the company to implement its strategy requires effective planning and management control systems. Therefore, the company's future growth and prospects may depend in part on its ability to manage this growth. There can be no guarantee that the company will achieve or effectively manage the level of success that the board expect. 

The company's growth strategy is centred around growing in established markets and targeting sectors in which we have strong credibility.

There is clear communication of strategy and alignment throughout the organisation, with the board responsible for delivering against defined strategic initiatives. The company's growth and expansion strategy is carefully budgeted and resourced for, with clear metrics for success.
 
Customer success is an integral part of the company's focus, with regular reviews of performance with the customer to ensure alignment with the customer's strategic imperatives in order to secure account retention.

Financial and non-financial key performance indicators
 

2025
2024
Increase/
(Decrease)
Turnover
£11.2m
£7.9m
42%
Profit/(loss) before tax
£9.7m
(£4.9m)
297%
Employees at year end
36
61
(41%)
Cash and cash equivalents
£3.2m
£0.4m
622%


Turnover for the year improved in 2025, driven by a new European client win.

Profit before tax was a function of increased turnover, improved cost performance within the business, and the recognition of the release of the lease liability as other administrative income.

Employee numbers were lower at the end of 2025, after the implementation of the back to profits plan, this resulted in the reduction of headcount through the year.

Cash and cash equivalents was up in 2025, driven by improved profitability, that was a function of an improved revenue outturn, better cost control, and more efficient control of working capital.


This report was approved by the board and signed on its behalf.



O W A Jones
Director

Date: 23 June 2026

Page 4

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
DIRECTORS' REPORT
FOR THE YEAR ENDED 31 DECEMBER 2025

The directors present their report and the financial statements for the year ended 31 December 2025.

Change of name

The company passed a special resolution on 15 April 2025 and changed its name on 28 April 2025 from Sondrel Limited to Aion Silicon Limited.

Principal activity

The company's principal activity is the execution of ASIC services, with a particular focus on artificial intelligence (Al), video, automotive and Internet of Things (loT) related applications. Customers include global Original Equipment Manufacture (OEM's), system houses and fabless semiconductor companies.

Results and dividends

The profit for the year, after taxation, amounted to £15,268,508 (2024: loss £4,077,885).

The directors did not recommend the payment of dividends in the year (2024: £Nil).

Directors

The directors who served during the year, and up to the date of signing this report, were:

G S Curren (resigned 30 January 2025)
O W A Jones (appointed 30 January 2025)
M S Julio (appointed 30 January 2025)

Directors' responsibilities statement

The directors are responsible for preparing the Strategic Report, the Directors' Report and the financial statements in accordance with applicable law and regulations.
 
Company law requires the directors to prepare financial statements for each financial year. Under that law the directors have elected to prepare the financial statements in accordance with United Kingdom Generally Accepted Accounting Practice (United Kingdom Accounting Standards and applicable law, including FRS 102 ‘The Financial Reporting Standard applicable in the UK and Republic of Ireland’). Under company law the directors must not approve the financial statements unless they are satisfied that they give a true and fair view of the state of affairs and profit or loss of the company for that period. In preparing these financial statements, the directors are required to:

select suitable accounting policies and then apply them consistently;

make judgements and accounting estimates that are reasonable and prudent; and

prepare the financial statements on the going concern basis unless it is inappropriate to presume that the company will continue in business.

The directors are responsible for keeping adequate accounting records that are sufficient to show and explain the company's transactions and disclose with reasonable accuracy at any time the financial position of the company and enable them to ensure that the financial statements comply with the Companies Act 2006They are also responsible for safeguarding the assets of the company and hence for taking reasonable steps for the prevention and detection of fraud and other irregularities.

Page 5

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
DIRECTORS' REPORT (CONTINUED)
FOR THE YEAR ENDED 31 DECEMBER 2025

Qualifying third party indemnity provisions

The company has granted an indemnity to the directors of the company against liability in respect of proceedings brought by third parties, subject to conditions set out in the Companies Act 2006. This qualifying third-party indemnity remains in force at the date of approving the Directors' Report.

Going concern

The company is a wholly owned subsidiary of Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited) (the 'group') and its financial position is dependent on the financial position of the group. At 31 December 2025, the company had cash reserves of £3,229,892 and net current assets of £4,755,102.

The directors have prepared detailed future forecasts for the group taking into account post year end trading conditions, which carefully consider group's ability to meet its future forecasted cash requirements. 

The directors have reviewed the cash flow forecasts for the group covering a period of at least 12 months from the date of the approval of the financial statements and together with the projected revenue and available cash reserves. They are confident that sufficient funding is available to support ongoing trading activity and investment plans for the business. 

Matters covered in the Strategic Report

As permitted under s414C(11) of the Companies Act 2006, the directors have included information in the Strategic Report that otherwise would be required under s416(4) to be disclosed in the Director's Report, including information in respect of future development and financial risks and policies.

Subsequent events

While the decision to close the group’s Xi’an office was taken during the year ended 31 December 2025, the orderly closure commenced after the reporting date and no substantive closure activities had occurred at year end. Actions taken after the reporting date include vacating the premises, terminating contracts, and initiating statutory tax deregistration. The closure is therefore treated as a non-adjusting post balance-sheet event, and the directors do not expect it to have a material impact on the group’s financial position or results for the year ended 31 December 2025.

Disclosure of information to auditor

The directors confirm that:
 
so far as each director is aware, there is no relevant audit information of which the company's auditor is unaware; and

the directors have taken all the steps that they ought to have taken as directors in order to make themselves aware of any relevant audit information and to establish that the company's auditor is aware of that information.

Auditor

The auditor, Grant Thornton UK LLP, was appointed during the period and will be proposed for reappointment in accordance with section 485 of the Companies Act 2006.

Page 6

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
DIRECTORS' REPORT (CONTINUED)
FOR THE YEAR ENDED 31 DECEMBER 2025

This report was approved by the board and signed on its behalf.
 





O W A Jones
Director

Date: 23 June 2026

Page 7

 

 
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INDEPENDENT AUDITOR'S REPORT TO THE MEMBERS OF AION SILICON LIMITED (FORMERLY SONDREL LIMITED)

Opinion


We have audited the financial statements of Aion Silicon Limited (the 'company') for the year ended 31 December 2025, which comprise the Statement of Comprehensive Income, the Balance Sheet, the Statement of Changes in Equity and notes to the financial statements, including a summary of significant accounting policies. The financial reporting framework that has been applied in their preparation is applicable law and United Kingdom Accounting Standards, including Financial Reporting Standard 102 ‘The Financial Reporting Standard applicable in the UK and Republic of Ireland’ (United Kingdom Generally Accepted Accounting Practice).


In our opinion:


the financial statements give a true and fair view of the state of the company's affairs as at 31 December 2025 and of its profit for the year then ended; 

the financial statements have been properly prepared in accordance with United Kingdom Generally Accepted Accounting Practice; and

the financial statements have been prepared in accordance with the requirements of the Companies Act 2006.



Basis for opinion


We conducted our audit in accordance with International Standards on Auditing (UK) (ISAs (UK)) and applicable law. Our responsibilities under those standards are further described in the ‘Auditor’s responsibilities for the audit of the financial statements’ section of our report. We are independent of the company in accordance with the ethical requirements that are relevant to our audit of the financial statements in the UK, including the FRC’s Ethical Standard, and we have fulfilled our other ethical responsibilities in accordance with these requirements. We believe that the audit evidence we have obtained is sufficient and appropriate to provide a basis for our opinion.


Conclusions relating to going concern


We are responsible for concluding on the appropriateness of the directors’ use of the going concern basis of accounting and, based on the audit evidence obtained, whether a material uncertainty exists related to events or conditions that may cast significant doubt on the company's ability to continue as a going concern. If we conclude that a material uncertainty exists, we are required to draw attention in our report to the related disclosures in the financial statements or, if such disclosures are inadequate, to modify the auditor’s opinion. Our conclusions are based on the audit evidence obtained up to the date of our report. However, future events or conditions may cause the company to cease to continue as a going concern.

In our evaluation of the directors’ conclusions, we considered the inherent risks associated with the company's business model including effects arising from macro-economic uncertainties such as the impact of cost inflation, global supply chain problems and geo-political uncertainty, we assessed and challenged the reasonableness of estimates made by the directors and the related disclosures and analysed how those risks might affect the company's financial resources or ability to continue operations over the going concern period.
Page 8


 
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INDEPENDENT AUDITOR'S REPORT TO THE MEMBERS OF AION SILICON LIMITED (FORMERLY SONDREL LIMITED) (CONTINUED)

Conclusions relating to going concern (continued)

In auditing the financial statements, we have concluded that the directors’ use of the going concern basis of accounting in the preparation of the financial statements is appropriate.

Based on the work we have performed, we have not identified any material uncertainties relating to events or conditions that, individually or collectively, may cast significant doubt on the company's ability to continue as a going concern for a period of at least twelve months from when the financial statements are authorised for issue.

Our responsibilities and the responsibilities of the directors with respect to going concern are described in the relevant sections of this report.


Other information


The other information comprises the information included in the Annual Report and financial statements, other than the financial statements and our Auditor’s Report thereon. The directors are responsible for the other information contained within the Annual Report and financial statements. Our opinion on the financial statements does not cover the other information and, except to the extent otherwise explicitly stated in our report, we do not express any form of assurance conclusion thereon. 


Our responsibility is to read the other information and, in doing so, consider whether the other information is materially inconsistent with the financial statements or our knowledge obtained in the audit or otherwise appears to be materially misstated. If we identify such material inconsistencies or apparent material misstatements, we are required to determine whether there is a material misstatement in the financial statements themselves. If, based on the work we have performed, we conclude that there is a material misstatement of this other information, we are required to report that fact.


We have nothing to report in this regard.


Opinions on other matters prescribed by the Companies Act 2006
 

In our opinion, based on the work undertaken in the course of the audit:


the information given in the Strategic Report and the Directors' Report for the financial year for which the financial statements are prepared is consistent with the financial statements; and

the Strategic Report and the Directors' Report have been prepared in accordance with applicable legal requirements.


Page 9


 
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INDEPENDENT AUDITOR'S REPORT TO THE MEMBERS OF AION SILICON LIMITED (FORMERLY SONDREL LIMITED) (CONTINUED)

Matter on which we are required to report under the Companies Act 2006
 

In the light of the knowledge and understanding of the company and its environment obtained in the course of the audit, we have not identified material misstatements in the Strategic Report or the Directors' Report.


Matters on which we are required to report by exception

We have nothing to report in respect of the following matters in relation to which the Companies Act 2006 requires us to report to you if, in our opinion:


adequate accounting records have not been kept, or returns adequate for our audit have not been received from branches not visited by us; or

the financial statements are not in agreement with the accounting records and returns; or

certain disclosures of directors' remuneration specified by law are not made; or

we have not received all the information and explanations we require for our audit.



Responsibilities of directors
 

As explained more fully in the Directors' Responsibilities Statement set out on page 5, the directors are responsible for the preparation of the financial statements and for being satisfied that they give a true and fair view, and for such internal control as the directors determine is necessary to enable the preparation of financial statements that are free from material misstatement, whether due to fraud or error.


In preparing the financial statements, the directors are responsible for assessing the company's ability to continue as a going concern, disclosing, as applicable, matters related to going concern and using the going concern basis of accounting unless the directors either intend to liquidate the company or to cease operations, or have no realistic alternative but to do so.


Page 10


 
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INDEPENDENT AUDITOR'S REPORT TO THE MEMBERS OF AION SILICON LIMITED (FORMERLY SONDREL LIMITED) (CONTINUED)

Auditor's responsibilities for the audit of the financial statements
 

Our objectives are to obtain reasonable assurance about whether the financial statements as a whole are free from material misstatement, whether due to fraud or error, and to issue an Auditor’s Report that includes our opinion. Reasonable assurance is a high level of assurance, but is not a guarantee that an audit conducted in accordance with ISAs (UK) will always detect a material misstatement when it exists. 

Misstatements can arise from fraud or error and are considered material if, individually or in the aggregate, they could reasonably be expected to influence the economic decisions of users taken on the basis of these financial statements.

Irregularities, including fraud, are instances of non-compliance with laws and regulations. The extent to which our procedures are capable of detecting irregularities, including fraud, is detailed below: 

We made enquiries of management and those charged with governance concerning the Company’s policies and procedures relating to:

°The identification, evaluation and compliance with laws and regulations;

°The detection of and response to the risks of fraud; and

°The establishment of internal controls designed to mitigate risks related to fraud or non-compliance with laws and regulations.

As part of the enquiries, management confirmed whether they were aware of any known instances of non-compliance with laws and regulations or whether they had any knowledge of actual, suspected or alleged fraud.

We corroborated the results of these enquiries through inspection of relevant supporting documentation.

We obtained an understanding of the legal and regulatory framework applicable to the Company and determined that the laws and regulations most significant in the context of the audit were those relating to the applicable financial reporting framework, namely FRS 102 and the Companies Act 2006. Our understanding was obtained through discussions with management, consideration of the Company’s internal policies and procedures and reference to our professional knowledge and experience of the sector. Compliance with these laws and regulations was considered throughout the audit, particularly when performing procedures over relevant financial statement balances, transactions and disclosures.

Relevant laws and regulations, together with identified fraud risks, were communicated to all members of the engagement team. The team remained alert throughout the audit to indications of fraud or non-compliance with laws and regulations.
Page 11


 
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INDEPENDENT AUDITOR'S REPORT TO THE MEMBERS OF AION SILICON LIMITED (FORMERLY SONDREL LIMITED) (CONTINUED)

Auditor's responsibilities for the audit of the financial statements (continued)

We assessed the susceptibility of the Company’s financial statements to material misstatement, including how fraud might occur, by evaluating management’s incentives and opportunities for manipulation of the financial statements. This included an evaluation of the risk of management override of controls. Based on the assessment, we identified principal risks as relating to:

°The significant risk of fraud arising from revenue recognised on a percentage completion basis for open contracts at year end where significant judgement is applied, and potentially unusual or non-standard revenue transactions identified through testing;

°Journal entries, with a focus on journals posted by senior personnel and journals posted by senior personnel and unusual journal postings to revenue or expenses, as well as large or unusual transactions based on our understanding of the Company and the nature of activity within the ledger; and

°Potential management bias in determining accounting estimates, in particular those relating to revenue recognition. In response, we evaluated the key judgements and assumptions applied by management in these areas and considered whether the resulting accounting treatment and related disclosures were appropriate and consistent with the applicable financial reporting framework.

Our audit procedures involved:

°Evaluation of the design effectiveness of controls that management has in place to prevent and detect fraud;

°Identifying unusual or high-risk journals to investigate and verify;

°Challenging assumptions and judgements made by management in it significant accounting estimates; and

°Assessing the extent of compliance with the relevant laws and regulations as part of our procedures on the related financial statement line item.

In addition, we completed audit procedures to conclude on the compliance of disclosures in the annual report and accounts with applicable financial reporting requirements.

These audit procedures were designed to provide reasonable assurance that the financial statements were free from fraud or error. The risk of not detecting a material misstatement due to fraud is higher than the risk of not detecting one resulting from error and detecting irregularities that result from fraud is inherently more difficult than detecting those that result from error, as fraud may involve collusion, deliberate concealment, forgery or intentional misrepresentations. Also, the further removed non-compliance with laws and regulations is from events and transactions reflected in the financial statements, the less likely we would become aware of it;
Page 12


 
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INDEPENDENT AUDITOR'S REPORT TO THE MEMBERS OF AION SILICON LIMITED (FORMERLY SONDREL LIMITED) (CONTINUED)

Auditor's responsibilities for the audit of the financial statements (continued)

The engagement partner’s assessment of the appropriateness of the collective competence and capabilities of the engagement teal included consideration of the engagement team’s: 

°Understanding of, and practical experience with, audit engagements of a similar nature and complexity, obtained through appropriate training and prior audit experience;

°Knowledge of the industry in which the Company operates; and

°Understanding of the legal and regulatory requirements specific to the entity, including the applicable legislation.

We did not identify any matters relating to non-compliance with laws and regulations or fraud.

A further description of our responsibilities for the audit of the financial statements is located on the Financial Reporting Council's website at: www.frc.org.uk/auditorsresponsibilities. This description forms part of our Auditor's Report.
 
Use of our report

This report is made solely to the company's members, as a body, in accordance with Chapter 3 of Part 16 of the Companies Act 2006Our audit work has been undertaken so that we might state to the company's members those matters we are required to state to them in an Auditor's Report and for no other purpose. To the fullest extent permitted by law, we do not accept or assume responsibility to anyone other than the company and the company's members as a body, for our audit work, for this report, or for the opinions we have formed.




Andrew Wood BA ACA
Senior Statutory Auditor
for and on behalf of Grant Thornton UK LLP
Statutory AuditorChartered Accountants
Reading

23 June 2026
Page 13

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
STATEMENT OF COMPREHENSIVE INCOME
FOR THE YEAR ENDED 31 DECEMBER 2025

2025
2024
Note
£
£

  

Turnover
  
11,216,653
7,891,170

Cost of sales
  
(7,671,063)
(8,738,284)

Gross profit/(loss)
  
3,545,590
(847,114)

Administrative expenses
  
(3,903,121)
(4,086,516)

Other administrative income
 5 
9,887,478
-

Other operating income
 6 
145,646
1,557,838

Operating profit/(loss)
 7 
9,675,593
(3,375,792)

Interest receivable and similar income
 11 
5,468
-

Interest payable and similar expenses
 12 
(29,883)
(1,513,916)

Profit/(loss) before tax
  
9,651,178
(4,889,708)

Tax on profit/(loss)
 13 
5,617,330
811,823

Profit/(loss) for the financial year
  
15,268,508
(4,077,885)

There were no recognised gains and losses for 2025 or 2024 other than those included in the Statement of Comprehensive Income.

There was no other comprehensive income for 2025 (2024: £Nil).

All activity in both the current and the prior year relates to continuing operations.

The notes on pages 17 to 36 form part of these financial statements.

Page 14

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
REGISTERED NUMBER:04491953

BALANCE SHEET
AS AT 31 DECEMBER 2025

2025
2024
Note
£
£

Fixed assets
  

Tangible assets
 15 
138,265
152,461

 
Current assets
  

Stocks
 17 
-
169,606

Debtors: amounts falling due within one year
 18 
9,439,364
6,077,569

Cash at bank and in hand
  
3,229,892
447,121

  
12,669,256
6,694,296

Creditors: amounts falling due within one year
 19 
(7,914,154)
(34,745,320)

Net current assets/(liabilities)
  
 
 
4,755,102
 
 
(28,051,024)

Total assets less current liabilities
  
4,893,367
(27,898,563)

Creditors: amounts falling due after more than one year
 20 
-
(7,124,841)

  

Net assets/(liabilities)
  
4,893,367
(35,023,404)


Capital and reserves
  

Called up share capital 
 23 
1,000
1,000

Capital contribution reserve
 24 
24,652,538
4,275

Profit and loss account
 24 
(19,760,171)
(35,028,679)

Total equity
  
4,893,367
(35,023,404)


The financial statements were approved and authorised for issue by the board and were signed on its behalf on 23 June 2026.




O W A Jones
Director

The notes on pages 17 to 36 form part of these financial statements.

Page 15

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 

STATEMENT OF CHANGES IN EQUITY
FOR THE YEAR ENDED 31 DECEMBER 2025


Called up share capital
Capital contribution reserve
Profit and loss account
Total equity

£
£
£
£


At 1 January 2024
1,000
4,275
(30,950,794)
(30,945,519)


Comprehensive loss for the year

Loss for the year
-
-
(4,077,885)
(4,077,885)



At 1 January 2025
1,000
4,275
(35,028,679)
(35,023,404)


Comprehensive income for the year

Profit for the year
-
-
15,268,508
15,268,508


Contributions by and distributions to owners

Release of intercompany loan balance
-
24,648,263
-
24,648,263


At 31 December 2025
1,000
24,652,538
(19,760,171)
4,893,367


The notes on pages 17 to 36 form part of these financial statements.

Page 16

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

1.


General information

Aion Silicon Limited (formerly Sondrel Limited) is a private company limited by shares, incorporated in England and Wales. Its registered number is 04491953, and its registered head office is located at 33 Great Portland Street, London, W1W 8QG.

2.Accounting policies

 
2.1

Basis of preparation of financial statements

The financial statements have been prepared under the historical cost convention unless otherwise specified within these accounting policies and in accordance with Financial Reporting Standard 102, the Financial Reporting Standard applicable in the UK and the Republic of Ireland and the Companies Act 2006.

The preparation of financial statements in compliance with FRS 102 requires the use of certain critical accounting estimates. It also requires management to exercise judgement in applying the company's accounting policies (see note 3).

The following principal accounting policies have been applied:

 
2.2

Financial Reporting Standard 102 - reduced disclosure exemptions

The company has taken advantage of the following disclosure exemptions in preparing these financial statements, as permitted by the FRS 102 "The Financial Reporting Standard applicable in the UK and Republic of Ireland":
the requirements of Section 7 Statement of Cash Flows;
the requirements of Section 3 Financial Statement Presentation paragraph 3.17(d);
the requirements of Section 11 Financial Instruments paragraphs 11.42, 11.44 to 11.45, 11.47, 11.48(a)(iii), 11.48(a)(iv), 11.48(b) and 11.48(c);
the requirements of Section 12 Other Financial Instruments paragraphs 12.26 to 12.27, 12.29(a), 12.29(b) and 12.29A;
the requirements of Section 26 Share-based Payment paragraphs 26.18(b), 26.19 to 26.21 and 26.23; and
the requirements of Section 33 Related Party Disclosures paragraph 33.7.

This information is included in the consolidated financial statements of Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited) as at 31 December 2025 and these financial statements may be obtained from Companies House.

 
2.3

Exemption from preparing consolidated financial statements

The company is a parent company that is also a subsidiary included in the consolidated financial statements of a larger group by a parent undertaking established under the law of any part of the United Kingdom and is therefore exempt from the requirement to prepare consolidated financial statements under section 400 of the Companies Act 2006.

Page 17

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)

 
2.4

Going concern

The company is a wholly owned subsidiary of Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited) (the 'group') and its financial position is dependent on the financial position of the group. At 31 December 2025, the company had cash reserves of £3,229,892 and net current assets of £4,755,102.

The directors have prepared detailed future forecasts for the group taking into account post year end trading conditions, which carefully consider group's ability to meet its future forecasted cash requirements. 

The directors have reviewed the cash flow forecasts for the group covering a period of at least 12 months from the date of the approval of the financial statements and together with the projected revenue and available cash reserves. They are confident that sufficient funding is available to support ongoing trading activity and investment plans for the business. 

 
2.5

Foreign currency translation

Functional and presentation currency

The company's functional and presentation currency is GBP and all values are rounded to the nearest pound (£) except where otherwise stated.

Transactions and balances

Foreign currency transactions are translated into the functional currency using the spot exchange rates at the dates of the transactions.

At each period end foreign currency monetary items are translated using the closing rate. Non-monetary items measured at historical cost are translated using the exchange rate at the date of the transaction and non-monetary items measured at fair value are measured using the exchange rate when fair value was determined.

Foreign exchange gains and losses resulting from the settlement of transactions and from the translation at period-end exchange rates of monetary assets and liabilities denominated in foreign currencies are recognised in profit or loss except when deferred in other comprehensive income as qualifying cash flow hedges.

Foreign exchange gains and losses that relate to borrowings and cash and cash equivalents are presented in the profit or loss within 'finance income or costs'. All other foreign exchange gains and losses are presented in profit or loss within 'other operating income'.

Page 18

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)

 
2.6

Turnover

Turnover is recognised to the extent that it is probable that the economic benefits will flow to the company and the turnover can be reliably measured. Turnover is measured as the fair value of the consideration received or receivable, excluding discounts, rebates, value added tax and other sales taxes. The following criteria must also be met before turnover is recognised:

Rendering of services

Turnover from a contract to provide services is recognised in the period in which the services are provided in accordance with the stage of completion of the contract when all of the following conditions are satisfied:
the amount of turnover can be measured reliably;
it is probable that the company will receive the consideration due under the contract;
the stage of completion of the contract at the end of the reporting period can be measured reliably; and
the costs incurred and the costs to complete the contract can be measured reliably.

Management are required to judge the level of completion of the contract in order to recognise both income and cost. The overall recognition of revenue will depend on the nature of the project and whether it is billed on a time and materials basis or, otherwise, on completion of pre-agreed project objectives.

The company maintains complete and accurate records of employees' time and expenditure for each project. This information is regularly assessed to determine the level of project completion, and thereby whether it is appropriate to recognise any revenue.

 
2.7

Leases

Rentals paid under operating leases are charged to the Statement of Comprehensive on a straight-line basis over the lease term.

Benefits received and receivable as an incentive to sign an operating lease are recognised on a straight-line basis over the lease term, unless another systematic basis is representative of the time pattern of the lessee's benefit from the use of the leased asset.

Assets acquired by finance lease are amortised over the shorter of the lease term and their useful lives. Finance leases are those where substantially all of the benefits and risks of ownership are assumed by the company. Obligations under such arrangements are considered lease liabilities by management and have been included in other creditors within creditors, net of the finance charge allocated to future periods. The finance element of the rental payment is charged to the Statement of Comprehensive Income to produce a constant periodic rate of charge on the net obligation outstanding in each period.

Page 19

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)

 
2.8

Employee benefits

Short-term employee benefits including holiday pay and annual bonuses are accrued as services are rendered. Contributions to defined contribution pension schemes are charged to the Statement of Comprehensive Income as they become payable in accordance with the rules of the scheme. Differences between contributions payable in the year and those actually paid are shown as either accruals or prepayments in the Balance Sheet.

 
2.9

Interest income

Interest income is recognised in the Statement of Comprehensive Income using the effective interest method.

 
2.10

Interest payable

Finance costs are charged to profit or loss over the term of the debt using the effective interest method so that the amount charged is at a constant rate on the carrying amount. Issue costs are initially recognised as a reduction in the proceeds of the associated capital instrument.

 
2.11

Current and deferred taxation

The tax expense for the year comprises current and deferred tax. Tax is recognised in the Statement of Comprehensive Income except that a charge attributable to an item of income and expense recognised as other comprehensive income or to an item recognised directly in equity is also recognised in other comprehensive income or directly in equity respectively.

The current income tax charge is calculated on the basis of tax rates and laws that have been enacted or substantively enacted by the Balance Sheet date in the countries where the company operates and generates income.

Deferred tax balances are recognised in respect of all timing differences that have originated but not reversed by the Balance Sheet date, except that:
The recognition of deferred tax assets is limited to the extent that it is probable that they will be recovered against the reversal of deferred tax liabilities or other future taxable profits; and
Any deferred tax balances are reversed if and when all conditions for retaining associated tax allowances have been met.

Deferred tax balances are not recognised in respect of permanent differences except in respect of business combinations, when deferred tax is recognised on the differences between the fair values of assets acquired and the future tax deductions available for them and the differences between the fair values of liabilities acquired and the amount that will be assessed for tax. Deferred tax is determined using tax rates and laws that have been enacted or substantively enacted by the reporting date.

Tax credits in relation to research and development expenditure are recognised in other operating income. All other amounts are recognised within tax on loss.

Page 20

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)

 
2.12

Intangible fixed assets

Intangible assets are initially recognised at cost. After recognition, under the cost model, intangible assets are measured at cost less any accumulated amortisation and any accumulated impairment losses.

All intangible assets are considered to have a finite useful life. If a reliable estimate of the useful life cannot be made, the useful life shall not exceed ten years.

Amortisation is included within "cost of sales" in the Statement of Comprehensive Income and is recognised as follows:
 
Software licences - On a usage basis over the length of licence agreement. Licence agreements have lives of between 1 and 3 years. 

Development costs - Not amortised until brought into use. The useful life is considered to be 3 years.
 
In any situation where there is a change in the pattern in which economic benefits are derived by the company from an intangible asset, management will review whether an accelerated amortisation is required.

 
2.13

Tangible fixed assets

Tangible fixed assets under the cost model are stated at historical cost less accumulated depreciation and any accumulated impairment losses. Historical cost includes expenditure that is directly attributable to bringing the asset to the location and condition necessary for it to be capable of operating in the manner intended by management.

Depreciation is charged so as to allocate the cost of assets less their residual value over their estimated useful lives, using the straight-line method.

Depreciation is included within "administrative expenses" in the Statement of Comprehensive Income and is recognised as follows:

Office equipment

3-10 years

The assets' residual values, useful lives and depreciation methods are reviewed, and adjusted prospectively if appropriate, or if there is an indication of a significant change since the last reporting date.

Gains and losses on disposals are determined by comparing the proceeds with the carrying amount and are recognised in the Statement of Comprehensive Income.

 
2.14

Valuation of investments

Investments in subsidiaries are measured at cost less accumulated impairment.

 
2.15

Stocks

Stocks relate to work in progress and are valued at the lower of cost and net realisable value. Costs incurred relate to direct materials.

Page 21

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)

 
2.16

Cash and cash equivalents

Cash is represented by cash in hand and deposits with financial institutions repayable without penalty on notice of not more than 24 hours. Cash equivalents are highly liquid investments that mature in no more than three months from the date of acquisition and that are readily convertible to known amounts of cash with insignificant risk of change in value.

 
2.17

Financial instruments

The company has elected to apply the provisions of Section 11 “Basic Financial Instruments” of FRS 102 to all of its financial instruments.

Financial instruments are recognised in the company's Balance Sheet when the company becomes party to the contractual provisions of the instrument.

Financial assets and liabilities are offset, with the net amounts presented in the financial statements, when there is a legally enforceable right to set off the recognised amounts and there is an intention to settle on a net basis or to realise the asset and settle the liability simultaneously.

Basic financial assets

Basic financial assets, which include trade and other debtors, cash and bank balances, are initially measured at their transaction price (adjusted for transaction costs except in the initial measurement of financial assets that are subsequently measured at fair value through profit and loss) and are subsequently carried at their amortised cost using the effective interest method, less any provision for impairment, unless the arrangement constitutes a financing transaction, where the transaction is measured at the present value of the future receipts discounted at a market rate of interest.

Discounting is omitted where the effect of discounting is immaterial. The company's cash and cash equivalents, trade and most other debtors due within the operating cycle fall into this category of financial instruments.

Impairment of financial assets

At the end of each reporting period financial assets measured at amortised cost are assessed for objective evidence of impairment. If an asset is impaired the impairment loss is the difference between the carrying amount and the present value of the estimated cash flows discounted at the asset’s original effective interest rate. The impairment loss is recognised in profit or loss. 

Financial assets are impaired when events, subsequent to their initial recognition, indicate the estimated future cash flows derived from the financial asset(s) have been adversely impacted. The impairment loss will be the difference between the current carrying amount and the present value of the future cash flows at the asset(s) original effective interest rate.

If there is a favourable change in relation to the events surrounding the impairment loss then the impairment can be reviewed for possible reversal. The reversal will not cause the current carrying amount to exceed the original carrying amount had the impairment not been recognised. The impairment reversal is recognised in the profit or loss.

Page 22

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

2.Accounting policies (continued)


2.17
Financial instruments (continued)

Basic financial liabilities

Financial liabilities and equity instruments are classified according to the substance of the contractual arrangements entered into. An equity instrument is any contract that evidences a residual interest in the assets of the company after the deduction of all its liabilities.

Basic financial liabilities, which include trade and other creditors, bank loans and other loans are initially measured at their transaction price (adjusting for transaction costs except in the initial measurement of financial liabilities that are subsequently measured at fair value through profit and loss). When this constitutes a financing transaction, whereby the debt instrument is measured at the present value of the future payments discounted at a market rate of interest, discounting is omitted where the effect of discounting is immaterial.
 
Debt instruments are subsequently carried at their amortised cost using the effective interest rate method.

Trade creditors are obligations to pay for goods and services that have been acquired in the ordinary course of business from suppliers. Trade creditors are classified as current liabilities if the payment is due within one year. If not, they represent non-current liabilities. Trade creditors are initially recognised at their transaction price and subsequently are measured at amortised cost using the effective interest method. Discounting is omitted where the effect of discounting is immaterial.

Derecognition of financial assets

Financial assets are derecognised when their contractual right to future cash flow expire, or are settled, or when the company transfers the asset and substantially all the risks and rewards of ownership to another party. If significant risks and rewards of ownership are retained after the transfer to another party, then the company will continue to recognise the value of the portion of the risks and rewards retained.

Derecognition of financial liabilities

Financial liabilities are derecognised when the company's contractual obligations expire or are discharged or cancelled.


3.


Judgements in applying accounting policies and key sources of estimation uncertainty

The preparation of the financial statements requires management to make judgements, estimates and assumptions that affect the application of accounting policies and reported amounts of assets, liabilities, income and expenses. Actual results may differ from these estimates.

Estimates and underlying assumptions are reviewed on an ongoing basis. Estimates are based on historical experience and other assumptions that are considered reasonable in the circumstances. The actual amount or values may vary in certain instances from the assumptions and estimates made. Changes will be recorded, with corresponding effect in the financial statements, when, and if, better information is obtained.

Critical judgements and sources of estimation uncertainty that management have made in the process of applying accounting policies disclosed herein and that have a significant effect on the amounts recognised in the financial statements relate to the following:
 
Page 23

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

3.Judgements in applying accounting policies (continued)

Estimates

Revenue recognition (see note 4)
The group recognises revenue over time for certain contracts based on the assessed stage of completion, which requires management judgement in estimating the proportion of work performed at the reporting date. This assessment is based on detailed project records, including time incurred and costs to date, together with management’s evaluation of the remaining effort required to complete the contract, and changes in these estimates may result in adjustments to revenue and profit.

Judgements

Recognition of Deferred Tax Assets (note 22)
Management has applied judgement in assessing the recognition of deferred tax assets which are recognised only to the extent that it is probable that future taxable profits will be available to utilise the accumulated losses. This assessment requires consideration of the forecasting of future profitability, the timing of customer contracts and the success of business plans.
 

4.


Turnover

An analysis of turnover by class of business is as follows:


2025
2024
£
£



Intercompany revenue
6,241,229
407,824

Design services
2,839,224
3,040,554

ASIC
1,653,560
2,115,647

NPI
-
1,496,676

Third party
-
820,256

Other
482,640
10,213

11,216,653
7,891,170

Analysis of turnover by country of destination:

2025
2024
£
£



United Kingdom
1,034,003
1,340,456

Rest of the World
683,857
619,684

Germany
-
2,732,012

France
3,257,564
2,279,054

USA
-
512,140

Spain
6,241,229
407,824

11,216,653
7,891,170
Page 24

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025


5.


Other administrative income

2025
2024
£
£


Finance lease liability
9,887,478
-

During the year, following the renegotiation of a significant finance lease for software, the associated lease liability was extinguished, resulting in the recognition of other administrative income. The related right-of-use asset had been fully amortised prior to the renegotiation and therefore did not offset this income.


6.


Other operating income

2025
2024
£
£

Research and development tax credit
145,646
1,557,838



7.


Operating profit/(loss)

The operating profit/(loss) is stated after charging/(crediting):

2025
2024
£
£

Exchange differences
83,156
227,310

Depreciation of tangible fixed assets
63,875
53,738

(Profit)/loss on disposal of tangible fixed assets
(6,082)
75,458

Other operating lease rentals
152,842
192,512

Impairment of investments (note 16)
-
386,636

Amortisation of intangible assets (note 14)
-
439,162

Impairment of amounts owed by group undertakings (note 18)
-
601,288

Research and development expenditure
3,193,035
3,371,163


8.


Auditor's remuneration

2025
2024
£
£

Fees payable to the company's auditor for the audit of the company's financial statements
50,000
86,625

The company has taken advantage of the exemption not to disclose amounts paid for non-audit services as these are disclosed in the group accounts of the parent company.

Page 25

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

9.


Employees

Staff costs, including directors' remuneration, were as follows:


2025
2024
£
£

Wages and salaries
2,636,150
4,166,859

Social security costs
409,123
491,970

Cost of defined contribution scheme
109,628
138,078

3,154,901
4,796,907


The average monthly number of employees, including the directors, during the year was as follows:


        2025
        2024
            No.
            No.







Engineering
17
42



Sales, administration and management
19
19

36
61


10.


Directors' remuneration

The directors have been remunerated through Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited). It is not practical to ascertain the proportion of director's emoluments that specifically relate to this company.



11.


Interest receivable and similar income

2025
2024
£
£


Bank interest receivable
5,468
-

Page 26

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

12.


Interest payable and similar expenses

2025
2024
£
£


Bank loan interest
-
91,631

Interest payable to group undertakings
27,999
28,076

Finance leases interest
-
1,394,209

Other interest payable
1,884
-

29,883
1,513,916


13.


Taxation


2025
2024
£
£



Adjustments in respect of previous periods
-
(783,409)

Total current tax
-
(783,409)

Deferred tax


Origination and reversal of timing differences
(5,733,112)
(28,414)

Adjustments in respect of prior periods
115,782
-

Total deferred tax
(5,617,330)
(28,414)


Tax on profit/(loss)
(5,617,330)
(811,823)
Page 27

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025
 
13.Taxation (continued)

Factors affecting tax charge for the year

The tax assessed for the year is lower than (2024: higher than) the standard rate of corporation tax in the UK of 25% (2024: 25.00%). The differences are explained below:

2025
2024
£
£


Profit/(loss) on ordinary activities before tax
9,651,178
(4,889,708)


Profit/(loss) on ordinary activities multiplied by standard rate of corporation tax in the UK of 25% (2024: 25.00%)
2,412,795
(1,222,427)

Effects of:


Tax effect of expenses that are not deductible in determining taxable profit
256,698
407,865

Tax effect of income not taxable in determining taxable profit
(99)
(6,255)

Adjustments to tax charge in respect of prior periods - current tax
(42,159)
(783,409)

R&D expenditure credits
(604,175)
(389,459)

Movement in deferred tax not recognised
(7,483,171)
1,181,862

Adjustments to tax charge in respect of prior periods
115,782
-

Group relief claimed
(273,001)
-

Total tax charge for the year
(5,617,330)
(811,823)


Factors that may affect future tax charges

Deferred tax balances have been measured at 25%, being the enacted UK corporation tax rate applicable to future periods at the Balance Sheet date.

Page 28

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

14.


Intangible assets




Software licences

£



Cost


At 1 January 2025
16,547,902


Disposals
(16,547,902)



At 31 December 2025

-



Amortisation


At 1 January 2025
16,547,902


Disposals
(16,547,902)



At 31 December 2025

-



Net book value



At 31 December 2025
-



At 31 December 2024
-

Amortisation charges for software licences represent cost relating directly to the company's revenue and, therefore, they have been charged through cost of sales in the Statement of Comprehensive Income.



Page 29

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

15.


Tangible fixed assets





Office equipment

£



Cost


At 1 January 2025
672,821


Additions
85,592


Disposals
(456,316)



At 31 December 2025

302,097



Depreciation


At 1 January 2025
520,360


Charge for the year on owned assets
63,875


Disposals
(420,403)



At 31 December 2025

163,832



Net book value



At 31 December 2025
138,265



At 31 December 2024
152,461

Page 30

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

16.


Fixed asset investments





Investments in subsidiary companies

£



Cost


At 1 January 2025
386,636



At 31 December 2025

386,636



Impairment


At 1 January 2025
386,636



At 31 December 2025

386,636



Net book value



At 31 December 2025
-



At 31 December 2024
-

Details of the company's subsidiaries at 31 December 2025 are as follows:



Name
Registered office
Class of shares
Holding

Sondrel (Xi'an) Company Limited
Room 2303-4, Capita Malls, 64A, Western Part of South Second Ring Road, Xi'an, China, 710065
Ordinary
100
%

While the decision to close the group’s Xi’an office was taken during the year ended 31 December 2025, the orderly closure commenced after the reporting date and no substantive closure activities had occurred at year end. Actions taken after the reporting date include vacating the premises, terminating contracts, and initiating statutory tax deregistration. The closure is therefore treated as a non-adjusting post balance sheet event, and the directors do not expect it to have a material impact on the group’s financial position or results for the year ended 31 December 2025.


Page 31

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

17.


Stocks

2025
2024
£
£

Work in progress
-
169,606


Work in progress represents goods purchased but not yet invoiceable. The balance above relates to a single customer contract.

Stocks are stated after provisions for impairment of £Nil 
(2024: £Nil). Impairment losses totalling £Nil (2024: £Nil) were recognised in profit and loss.


18.


Debtors: amounts falling due within one year

2025
2024
£
£


Trade debtors
242,381
609,611

Amounts owed by group undertakings
2,354,490
729,339

Other debtors
55,308
-

Prepayments and accrued income
734,425
1,099,726

Tax recoverable
435,430
3,638,893

Deferred taxation (note 22)
5,617,330
-

9,439,364
6,077,569


Trade debtors are stated after provisions for impairment of £12,155 (2024: £41,578).

Amounts owed by group undertakings are stated after provision for impairment of £Nil 
(2024: £601,288).

Amounts owed by group undertakings are non-interest bearing, unsecured and repayable on demand.


19.


Creditors: amounts falling due within one year

2025
2024
£
£

Trade creditors
9,101
486,915

Amounts owed to group undertakings
3,385,794
29,306,244

Other taxation and social security
70,389
417,355

Other creditors
-
2,793,319

Accruals and deferred income
4,448,870
1,741,487

7,914,154
34,745,320


Page 32

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

19.Creditors: amounts falling due within one year (continued)

Amounts owed to group undertakings are non-interest bearing, unsecured and repayable on demand.

Other creditors include £Nil 
(2024: £2,762,637) in respect of obligations relating to finance leases, payable in instalments and net of finance charges allocated to future periods. The contractual undiscounted lease payments due within one year are £Nil (2024: £4,091,162). The finance lease is secured to the assets to which it relates. 

In March 2024 a contract for software was renegotiated resulting in a remeasurement of the outstanding finance lease liability and related assets held under hire purchase agreements. This resulted in a decrease to the liability of £3,803,655 and a decrease to the asset of £2,142,387 for the year ending 31 December 2024.

During the year, amounts of £24,648,262 owed by the company to parent entity were formally released by the parent. As a result, the related intercompany balances were extinguished during the year, the release did not give rise to any cash flows for the company and the amounts previously owed have been recognised directly in equity as a transaction with group undertakings.





20.


Creditors: amounts falling due after more than one year

2025
2024
£
£

Other creditors
-
7,124,841


Other creditors include £Nil (2024: £7,124,841) in respect of obligations relating to finance leases, payable in instalments and net of finance charges allocated to future periods. The contractual undiscounted lease payments due after one year and before two years are £Nil (2024: £3,474,590). The contractual undiscounted lease payments due after two years and before five years are £Nil (2024: £5,491,193). The finance lease is secured to the assets to which it relates.


21.


Hire purchase and finance leases


Minimum lease payments under hire purchase fall due as follows:

2025
2024
£
£


Within one year
-
2,762,637

Between 1-2 years
-
3,474,590

Between 2-5 years
-
5,491,193

-
11,728,420

Page 33

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

22.


Deferred taxation




2025


£






At beginning of year
-


Charged to profit or loss
5,617,330



At end of year
5,617,330

The deferred tax asset is made up as follows:

2025
2024
£
£


Fixed asset timing differences
(33,631)
-

Short term timing differences
17,597
-

Losses and other deductions
5,633,364
-


23.


Share capital

2025
2024
£
£
Allotted, called up and fully paid



1,000,000 (2024: 1,000,000) Ordinary shares of £0.001 each
1,000
1,000


There is a single class of ordinary shares. There are no restrictions on dividends and the repayment of capital.


24.


Reserves

The company's capital and reserves are as follows:

Capital contribution reserve

This reserve relates to capital contributions from Aion Silicon Holdings Limited (Formerly Sondrel Holdings Limited) ("the parent") in respect of share options granted by the parent to employees of the company.

Profit and loss account

This reserve relates to the cumulative profit or loss less amounts distributed to shareholders.

Page 34

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

25.


Pension commitments

The company operates a defined contributions pension scheme. The assets of the scheme are held separately from those of the company in an independently administered fund. The pension cost charge represents contributions payable by the company to the fund and amounted to £109,628 (2024: £138,078). Contributions totalling £70,389 (2024: £30,682) were payable to the fund at the Balance Sheet date and are included in creditors.


26.


Commitments under operating leases

At the reporting date the company had future minimum lease payments due under non-cancellable operating leases for each of the following periods:

2025
2024
£
£

Land and buildings


Not later than 1 year
27,900
159,486


27.Other financial commitments

The company entered into a bank cross guarantee with its fellow group entities. The assets of the company were pledged as security for the bank loans and overdraft facility by way of fixed and floating charge. During the prior year, two charges that were delivered on 26 July 2023 and 28 September 2023 were satisfied on 6 August 2024. 

During the prior year, the company's immediate parent undertaking, Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited) entered into separate loan arrangements with ROX Equity Partners Limited and ROX Technologies Ltd. Charges over the company's assets were registered at Companies House on 5 March 2024 and 12 November 2024 as a result of these loan arrangements and are currently outstanding.


28.


Related party transactions

The company has taken advantage of the exemption in FRS 102 Section 33.1 A to not disclose transactions with wholly owned group entities.


29.


Subsequent events

While the decision to close the group’s Xi’an office was taken during the year ended 31 December 2025, the orderly closure commenced after the reporting date and no substantive closure activities had occurred at year end. Actions taken after the reporting date include vacating the premises, terminating contracts, and initiating statutory tax deregistration. The closure is therefore treated as a non-adjusting post balance-sheet event, and the directors do not expect it to have a material impact on the group’s financial position or results for the year ended 31 December 2025.

Page 35

 
AION SILICON LIMITED (FORMERLY SONDREL LIMITED)
 
 
NOTES TO THE FINANCIAL STATEMENTS
FOR THE YEAR ENDED 31 DECEMBER 2025

30.


Controlling party

The immediate and ultimate parent undertaking is Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited), a company registered in England and Wales. 

The largest and smallest group of undertakings for which consolidated accounts for the year ended 31 December 2025 have been drawn up, is that headed by Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited). The registered office address of Aion Silicon Holdings Limited (formerly Sondrel (Holdings) Limited) is 33 Great Portland Street, London, England, W1W 8QG. Copies of the consolidated accounts are available from Companies House. 

In the opinion of the directors, ROX Technologies Ltd is the ultimate controlling party.

Page 36