CBT Summer Conference 2025

About the Event

27 June 09:30 to 18:00    Saïd Business School, Oxford OX1 1HP

 

The conference focused on uncertainty in business taxation. 

Businesses face a landscape of complex, new, and untested law, including that emerging from the GloBE project. Although it has been apparent for some time that Pillar 1 reforms were unlikely to succeed, leading instead to a proliferation of uncoordinated Digital Services Taxes (DSTs), Donald Trump’s Executive Order of 20 January 2025 threw the broader reform process into tailspin. The path forward remains highly uncertain. 

In addition to uncertainty over substantive tax policy there is also uncertainty about global tax governance. While some countries prefer the long-standing status quo – with the OECD continuing to lead in setting international business tax standards - other countries advocate for substantial changes that may take us into unchartered territory. Overall, the global tax landscape is permeated with uncertainty. 

This year’s CBT Annual Summer Conference focuses specifically on business taxation in uncertain times. It will begin with a panel exploring the implications of uncertainty—particularly tax-related uncertainty—on business operations and investment decisions. Subsequently, the conference will delve deeper into two key areas characterized by exceptional uncertainty: GloBE and potential destination-based taxes – including Pillar 1, DSTs and tariffs. The conference will conclude by addressing the immediate and longer-term prospects. Looking towards the immediate future, the final panel will discuss how businesses and policy makers are to navigate the next 3 to 4 years. Looking beyond that, it will discuss whether any of the current sources of uncertainty could lead to longer-lasting changes in business tax practices and the policymaking processes themselves. 

We are pleased to announce that this year’s Annual Conference will include the first Loughlin Hickey Annual Lecture, which is kindly sponsored by KPMG. This year’s lecture ‘Tariffs and other Destination-based taxes (in times of uncertainty)’ will be delivered by Professor Michael Devereux (Oxford University Centre for Business Taxation). 

Speakers included:

  • James Murray MP (Exchequer Secretary to the Treasury)
  • Achim Pross (OECD)

 

Programme


Session 1:  Sources and consequences of uncertainty


Chair: Niels Johannesen (Oxford University Centre for Business Taxation)

  • Welcome from Niels Johannesen (Oxford University Centre for Business Taxation) 

  • Economic evidence on the consequences of uncertainty for investment and growth

Irem Güçeri (University of Oxford)  


Session 2:  GloBE and uncertainty


Chair: Giorgia Maffini (PwC)

  • Uncertainty around impact/revenues. What is the likely impact of GloBE?

Niels Johannesen (Oxford University Centre for Business Taxation) 


  • What issues still need to be ironed out?

Michael Hashemi (HMRC) 
Scott Huxford (OECD)
Christoph Wissmann (P&G) 


  • Developments in the US and their impact on GloBE

Stephen Shay (Boston Law School) 


Session 3:  Tariffs and other Destination-based taxes (in a world of uncertainty) 


Chair: David Linke (KPMG)

  • Loughlin Hickey Annual Lecture: Michael Devereux (Oxford University Centre for Business Taxation)

Session 4:  Moving forward in a world of uncertainty


Chair: John Vella (Oxford University Centre for Business Taxation)

  • UK perspective

James Murray MP (Exchequer Secretary to the Treasury)


  • International perspective

Mindy Herzfeld (University of Florida) 
Jonathan Lacey (Microsoft) 
Achim Pross (OECD) 
Grant Wardell-Johnson (KPMG)