Stuart O’Brien



Stuart has experience of a broad range of pension related matters, advising employers and trustees alike with a particular emphasis on finance and investment issues.  This includes buy-ins and buy-outs, de-risking and advising on the legal aspects of scheme funding issues, including the use of contingent assets.

Stuart is a leading industry figure for environmental, social and corporate governance (ESG) and climate change issues, stewardship, responsible and impact investing. He chairs the Pensions Climate Risk Industry Group and sits on high profile committees including at the PLSA. He also provides legal input to the City of London Green Finance working group, the Institute and Faculty of Actuaries working group on climate change and the newly created Impact Investment Institute.

Stuart’s advice includes making changes to pension benefits (including the closure of schemes to future accrual), liability management exercises including pension increase exchange and pre-retirement transfer exercises, as well as scheme mergers, demergers, and solvent and insolvent wind-ups.

He also has significant expertise advising on the pensions aspects of corporate mergers, acquisitions and restructuring, dealing with Pensions Regulator clearance, section 75 debts, and apportionment and withdrawal arrangements.

Stuart is chair of the TCFD guidance working group (Taskforce on Climate-related Financial Disclosures), and a member of the Security of DC Assets Working Party.

Recent experience

  • Assisting clients with the settlement of deferred and pensioner liabilities via buy-in and buy-out bulk annuity transactions totalling more than £2bn in aggregate, including assisting the trustees of the Friends Provident Pension Scheme on their ground breaking collateralised buy-in of pensioner liabilities with Aviva in 2008, as well as numerous other transactions with all major insurers over the last decade
  • Advising Trustees on ESG matters in investment strategy and decision making
  • Advising Trustees on DC investment issues, including the use of platform structures, asset security and the transition of member funds
  • Advising Trustees on the creation of a £300m bespoke contingent funding vehicle with standalone investment management and custody agreements.

Memberships and Qualifications

Membership of professional bodies:
Association of Pension Lawyers
(Full Member and Investment Committee Member)
Pensions Management Institute (Ordinary Member)

Career history

Qualified: 2003, England & Wales

Pensions experience since: 2003

Joined Sackers: 2003, Associate: 2008

Joined partnership/LLP: 2011

Employers: Hammonds (2001-2003)

Academic history


Nottingham Law School (2000-2001)
University of Texas Law School, Austin, USA (1998-1999)
University of Nottingham (1996-2000)

Degree: LLB (with merit in American Law), Nottingham University
Legal Practice Course

Further Information


  • “I have always been impressed by Stuart’s ability to explain complex matters in plain English, and for his pragmatic approach. As a car manufacturer, costs will always be an issue, and Stuart carries out work for us mindful of the need to contain costs, whilst providing an excellent service”.
    Roland Craven, Senior Controller, Pensions Section, Nissan Motor Manufacturing (UK) Ltd
  • He is “pragmatic and does not waffle”. Legal 500 2014 recommended lawyer


Contingent assets

DB Investment

DC Investment

Banking and finance

Buy-ins and buy-outs

ESG and climate change

Latest News & Media

Sackers named Boutique Law Firm of the Year at Legal Business Awards 2020

Stuart O’Brien speaks at PensionsAge Annual Conference on climate risk reporting in 2021 SIPs

Sackers advises on Siemens £530m buy-in

Stuart O’Brien contributes to PLSA guide on new trustee investment disclosure duties

Stuart O’Brien comments on ESG and climate change risk in Professional Pensions

Stuart O’Brien comments on TCFD reporting by pension trustees

Stuart O’Brien explains why all trustees need to think about climate change

PCRIG launches consultation on new guide to climate-related financial risks for pension schemes

Sackers launches latest guidance on ESG and climate change

Guy Opperman praises Stuart O’Brien’s role in delivering the Pensions Climate Risk Industry Group guidance for pension schemes

Latest Knowledge

Consultation: taking action on climate risk

Finance & investment briefing – September 2020

Reminder! Changes to Investment disclosure and governance

Finance & investment briefing – June 2020

ESG and climate change for pension funds

Buy-ins, buy-outs and longevity solutions

Finance & investment briefing – March 2020

Sackers ESG survey for pension schemes: Summary report – key themes and Sackers views

Buy-ins, buy-outs and longevity transactions – A guide for trustees

ESG and climate change for pension funds – Putting the law into practice