Specialist and experienced

Our People

Executive Team

Mike Selby

After graduating from Oxford University in 2002, Mike enjoyed a successful spell with a major benefits consultancy, playing key roles in actuarial, consulting and data management disciplines.

With a strong background in data management, systems and software development, Mike started to develop pensions modelling software, Mantle in 2010, which he now concentrates on full time, joining Mantle Services in May 2014. 

DDI: +44 (0) 14 1343 9191


Brian Spence

Brian is a Fellow of the Institute and Faculty of Actuaries and has been working in pensions since 1987 and qualified as an actuary in 1990.

Brian is a founder of actuaries Spence & Partners Limited, director of independent trustee Dalriada Trustees Limited and director of Mantle Services Limited and Mantle Hosting Limited, all members of the 3173 Limited group of companies.

DDI: +44 (0) 20 3691 2947


Graeme Riddoch

Graeme is responsible for driving the Mantle software business to realise its full potential. This includes setting the overall direction, identifying new opportunities and product developments.

Graeme joined in November 2019 and has spent the last 10 years in Fintech. Most recently he was the founding director of HUB Pension Solutions a ground breaking DB member option business with a big focus on member engagement.

DDI: +44 (0) 20 3691 2940

Neil Buchanan

Neil is a Fellow of the Institute and Faculty of Actuaries with over 12 years’ experience in the pensions industry. With his actuarial background, Neil has extensive experience in pension scheme valuations, pension scheme accounting disclosures and ad-hoc project work such as scheme asset-liability modelling, monitoring investment performance and member option exercises.

Neil joined Mantle Services Limited in April 2022 and is responsible for the leadership and operational management of Mantle Services Limited.

DDI: +44 (0) 28 9041 2028


James Whittingham

James is the Chief Commercial Officer for Mantle. James is an entrepreneurial business leader with a track record of launching and developing technology businesses across sectors including Fintech, Payments, EdTech, Media and Sport, and Cloud Services. With over 20 years of executive leadership experience,
James has been a founder, investor, Commercial lead, and CEO of numerous successful business ventures. 

James has a degree in Computer Science and a Masters in Management and Finance from the University of Cambridge, and is a Trustee of Coram children’s charity. 

DDI: +44 (0) 28 9521 0155


Business Support

Martin Mellon

Martin is responsible for leading a seamless transition process for onboarding new clients. Martin works alongside the Service Delivery, Engineering and Support teams with client satisfaction as a key focus. Martin has over 35 years’ experience in the Software Delivery Life Cycle, and believes in a people centric focus.

Martin started in Software Delivery as an Assembler Programmer and has developed and lead multi-disciplinary teams and projects across the globe including US, Romania, Brazil, Pakistan, India, Colombia and Africa.

Martin’s experience spans from the start-up of wholly owned subsidiaries of US companies in Northern Ireland and being involved in “bleeding edge” technology in varied fields from cryptocurrency to genomics.

DDI: +44 (0) 28 9521 0111


Rachael Watt

Rachael holds a BSc in Business Economics from Queens University and a MSc in Management and Corporate Governance from the University of Ulster

Rachael has 10 years experience in the IT Industry working in Quality, Compliance and Customer Service roles, gaining a range of experience with ISO standards, Improvement & Quality methodologies, in both the corporate and public sector.

Rachael is responsible for all aspects of Service Delivery for Mantle, ensuring our Service Management Strategy maintains a specific focus on performance management, customer satisfaction and continuous improvement. 

DDI: +44 (0) 28 9521 0143 


Adam Stephenson

Adam is a Graduate Business Analyst and is part of the Data Services Team within the Mantle brand. Adam brings an actuarial background to the team, offering experience from spending placement within the Actuarial team.

He is also managing the MPP project, carrying out actions on the actuarial, admin and data services side. Adam is also currently sitting CPC exams.

DDI: +44 (0) 28 9041 2886



Aisling Kerr

Aisling joined Mantle having recently graduated with a BSc Finance from Queen’s University Belfast.  She works within the Data Services team which is responsible for Mantles functionality and managing the online support portal.

DDI: +44 (0) 28 9521 0211


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Dawn Watson

Dawn is a Fellow of the Pensions Management Institute with over 15 years experience in pensions administration and has worked for a number of third party administrators during that time.

Dawn joins Mantle, having worked within the Pensions Delivery Function at Spence and Partners between 2017 and 2021.

Dawn provides administration consulting services to a number of schemes with particular expertise in data quality, scheme transitions and process improvements.

DDI: +44 (0) 14 1433 8370

Matthew Leathem

Matthew is a Fellow of the Institute and Faculty of Actuaries and leads our actuarial team. Matthew brings a wealth of expertise and experience to the team with a background in both trustee advisory and corporate advisory contexts for pension schemes.

Matthew has played a key role in shaping the actuarial and investment functionality of Mantle. He has extensive experience supporting both consultancies and pension schemes as they transition to new actuarial platforms.

DDI: +44 (0) 28 9041 2882

Gavin Downey

Gavin entered the pensions industry in 2014 working as an actuary. He is involved in the installation and testing of benefit calculations for schemes on Mantle. He also provides guidance and support to  clients to ensure they are using Mantle effectively.

DDI: +44 (0) 28 9521 0298



Aaron Copeland

Aaron completed an undergraduate degree in Accounting and Finance at the University of Glasgow, followed by a Masters degree in Actuarial Science at Heriot-Watt University in Edinburgh.

Due to Aaron’s experience of Mantle Actuary he assists in developing and testing new functionality. He is now primarily involved in transitioning, testing and supporting Mantle Actuary clients.

DDI: +44 (0) 14 1331 9982

Ciaran Harris

Ciaran is a qualified actuary and an experienced member of our actuarial team. He graduated from the University of Edinburgh with a BSc in Mathematics and Statistics and has since gained a wealth of experience in the defined benefit pension industry across both trustee advisory and corporate advisory areas. 

He is one of our actuarial experts at Mantle and plays a leading role in both testing new features of the system and providing actuarial support to users as they
transition to using Mantle as their actuarial system.

DDI: +44 (0) 28 9041 2016

Clar Christie Mantle

Clár Christie

Clár Christie is an experienced actuary with valuable insights in advising both trustee and corporate clients. Currently serving as a dedicated Actuarial Specialist at Mantle, providing input into the development of the actuarial functionality on Mantle and supporting actuarial users.

Clár’s current focus is on the onboarding of new clients and installation of new Schemes onto the platform and her work centres on optimising efficiency, governance, and customer experiences. 

DDI: +44 (0) 28 9521 0294


Chris Tucker

Chris is a Senior Client Manager with over 15 years experience working in Defined Benefit and Defined Contribution pensions. Chris has extensive experience working with pension schemes, their trustees and key stakeholders on all matters relating to management and governance.

Chris joined Mantle in 2022 having previously worked for a large Consultancy firm as a Consultant and Client Manager. Chris acts as a first point of contact, responsible for managing client relationships throughout installation and beyond and has an overview of all services provided by Mantle.

Chris is an Associate member of the Pensions Management Institute.

DDI: +44 (0) 14 1331 9977

Eoghan Adams

DDI: +44 (0) 28 9521 0289


Dennis Mincher

Dennis is an integral part of Mantle, serving as a Senior Data and Systems Analyst with a wealth of experience in data management, actuarial processes and pension scheme administration. He is responsible for all aspects of data management, including scheme migrations; system configuration and testing; benefit analysis; and data rectification.

Dennis holds a BSc in Physics with Astrophysics from Queen’s University Belfast and has obtained professional qualifications in Data Analytics and Project Management alongside being a Certificate Member of the Pensions Management Institute.

DDI: +44 (0) 28 9041 2007

Harry O'Connell

Harry has built up experience in IT and pension sectors, having held roles as a software developer and as an actuarial technician.

Harry is actively involved in software development and provides information security support to a number of companies. Harry has also begun studying towards professional actuarial qualifications.

DDI: +44 (0) 28 9041 2892


Barry Stevenson

Barry is a Fellow of the Institute and Faculty of Actuaries with over 20 years of actuarial experience in the life insurance sector, previously holding roles as a liability modelling specialist in major life actuarial consultancies and top UK life insurance companies.

Barry has also previously held the position of Chief Examiner for the UK Actuarial Profession.

Barry joined in 2021 and works as a systems and software developer with a particular focus on AI and machine learning solutions in the pensions landscape.

DDI: +44 (0) 28 9041 2020

Jason Swann

Jason entered the pension industry in 2006, working as a pension scheme administrator. He has particular expertise in benefit calculation and scheme take-on work. 

Jason is studying toward his professional qualifications with the Pensions Management Institute.

Jason is actively involved in all aspects of data management and provides administration consulting services to a number of pension schemes.

DDI: +44 (0) 28 9041 6497

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Kev Seenan

Kevin is a Software Developer at Mantle working on providing new products to customers. He has a real drive for this and attended an intensive 16-week Software Development course to gain the skills required to begin a new career as a Software Developer.

DDI: +44 (0) 14 1370 0022

Patrick Lohan

Patrick is a Software Developer at Mantle.

DDI: +44 (0) 14 1370 0021

Laura McCartney

Laura McCartney recently graduated from Loughborough University with a PhD in Theoretical Computer Science and a BSc in Computer Science & Mathematics and is working towards qualifying with the Institute and Faculty of Actuaries.

Laura is actively involved in software development and has a strong understanding of good coding practices, implementing these effectively in several different programming languages.

Laura has experience providing technical support in an IT department, with a particular focus on streamlining reporting systems and improving online efficiency. 

DDI: +44 (0) 12 1389 2315


Susan McFarlane​

Susan leads the marketing function for Mantle and is supported by the marketing team, handling all promotional activity including business development, marketing, events and PR.

Susan has spent over 15 years working in marketing across a range of industries and sectors both in the UK and overseas.

DDI: +44 (0) 20 3691 2946

Lets talk about you​

To discuss how we can help with your company pensions and challenges, please contact us.

For general enquires enquiries@mantleservices.com

Linen Loft
27-37 Adelaide Street
Belfast , BT2 8FE UK
+44 28 9041 2888