UCL Faculty of Laws


Online | Time for a Tertium Quid

09 March 2023, 6:00 pm–7:00 pm

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Current Legal Problems Lecture Series 2021-22

Event Information

Open to



UCL Laws

Speaker: Prof. Sarah Green (Law Commissioner for Commercial and Common Law)
Chair: The Hon. Mrs Justice Cockerill DBE (Judge of the Commercial Court)

About the Lecture

“All personal things are either in possession or action. The law knows no tertium quid between the two." (Fry LJ in Colonial Bank v. Whinney (1885))

The traditional dichotomy between choses in possession and choses in action is not fit for purpose in the digital age.  It fails to categorise exhaustively the full range of things in which property rights ought to vest.  The historical association between tangibility and possessability is no surprise:  never before the digital age could we “hold” anything that was not tangible.  Nor did we want to.  This led to the unexamined development of tangibility as a proxy for possessability.  Now, however, technology has created assets that, whilst not being tangible in the conventional sense of being able to be perceived with the naked senses, are nevertheless distinct from choses in action:  they have an existence independent of persons and the legal system; they are amenable to exclusive possession; and are fully divestible on transfer.  They are not, therefore, choses in action.  Are they, therefore, choses in possession?  Or something else?  This lecture will explain why it is time for a tertium quid. 

About the Speaker

Professor Green was appointed as Law Commissioner for Commercial and Common law on 01 January 2020. She was previously Professor of Private Law at the University of Bristol.  Prior to that, she was Professor of the Law of Obligations at the University of Oxford, having been a lecturer at the University of Birmingham from 2001 – 2010.  Before embarking on her academic career, she was a software consultant at Accenture.  Professor Green has written books and articles on a variety of issues including virtual currencies, blockchain issues surrounding intermediated securities, smart contracts, sale of goods law as applicable to digitised assets, negligence and wage theft.


This event will be delivered via Zoom Webinar. Attendee cameras and microphones will be turned off but they will be able to put questions to the panel via the Q&A box. You will receive your zoom joining link 48-hours before the start of the event. Contact the Laws Events team (laws-events@ucl.ac.uk) if you have not receive the link.

About Current Legal Problems

The Current Legal Problems (CLP) lecture series and annual volume was established over fifty five years ago at the Faculty of Laws, University College London and is recognised as a major reference point for legal scholarship.

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