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Portrait ofJeremy Mash

Jeremy Mash


CMS Cameron McKenna Nabarro Olswang LLP
Cannon Place
78 Cannon Street
United Kingdom
Languages English

Jeremy Mash is a partner in the Commercial Dispute Resolution Team in London. He has over twenty years of experience working on high value disputes, including domestic and cross-border litigation, international arbitration and other dispute resolution methods. He regularly advises UK and international clients on M&A claims, shareholder disputes, outsourcing projects, private equity and venture capital, fraud claims and a wide range of other issues. He has specialised in the technology, media and telecoms industries throughout his career and was previously a partner at Olswang prior to its merger into CMS.

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“A first-class litigator with all-round skills”

Legal 500, 2018

"The practice ‘always delivers’…….. Jeremy Mash is recommended."

Legal 500, 2015

"Identified as a key player in technology, media and real estate disputes. Highly regarded for its large-scale litigation capacity and ability to take on challenging mandates. Stable client base includes numerous household names. Jeremy Mash is praised for his availability and accessibility. Sources also point to his ability to deliver pragmatic advice."

Chambers, 2014

"Jeremy Mash is recommended."

Legal 500, 2014

"Jeremy Mash is 'a star'."

Legal 500, 2013

"Jeremy is highly rated."

Legal 500, 2013

Relevant experience

  • Slater & Gordon on its GBP 637m claim against Watchstone Group arising from the sale of the former Quindell legal services business.
  • A Leading IT services supplier on a GBP 300m dispute with a UK mobile operator relating to transformation of legacy IT infrastructure.
  • Shareholders in USD 500m dispute relating to shares in one of the largest construction companies in the Middle East.
  • A leading sports car manufacturer on a dispute relating to the design and development of a racing engine.
  • The BBC on challenges to the reforms implemented to address its GBP 3bn pension deficit.
  • Kaupthing on a EUR 3bn portfolio of derivatives and structured finance disputes following the Icelandic banking crisis.
  • The Defendants in the Masri v Consolidated Contractors litigation relating to cross-border enforcement of judgments.
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  • 1999 – Admitted as a solicitor in England and Wales
  • 1997 – LPC, College of Law
  • 1994 - BA Hons, Oxford University, Oxford
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The role of arbitrators in the settlement process
In any dispute, parties are free to settle at any time. In order to avoid the time, cost and risk associated with pursuing or defending arbitration proceedings to their conclusion, it is generally in...
The role of arbitrators in the settlement process
Hypothesis: Most arbitration rules do not require tribunals to encourage or facilitate settlement In any dispute, parties are free to settle at any time. In order to avoid the time, cost and risk associated with pursuing or defending litigation or arbitration proceedings to their conclusion, it is generally in the best interests of both parties to consider all forms of alternative dispute resolution (ADR) mechanisms, with a view to achieving settlement.   But what role, if any, does (or should) a tribunal play in this process? In England and Wales, it has long been understood that the courts should play a role in promoting and encouraging the early settlement of cases. Under the English Civil Procedure Rules, courts are required to actively manage cases to further the overriding objective of dealing with cases justly and at proportionate cost.  Active case management expressly includes “helping the parties to settle the whole or part of the case” (CPR r.1.4(f)). By contrast, arbitrators in many jurisdictions have traditionally held the view that their primary duty is to determine cases and issue enforceable awards, believing that interfering with the parties’ right to freely negotiate between themselves would undermine the role of a tribunal as a neutral and impartial forum. Legal practitioners have grappled for some time with the question of whether an arbitrator’s role does, and in fact should, go beyond the mere determination of the merits of a case and if so, how involved they should be in the parties’ decision-making. In this fifth and final article in a series of data sheets exploring arbitration topics as part of our Data Driven Disputes campaign, we posed the hypothesis that most arbitral institutions adhere to the traditional mindset of non-in­ter­ven­tion, and accordingly do not contain provisions in their rules mandating that tribunals encourage or facilitate settlement. Research and methodology To investigate, we analysed the rules of 29 arbitral institutions around the world and spoke to some of those institutions about whether they were seeing any increase in parties settling and, if so,  whether there was any one factor to which they attributed that increase.
Making efficiency a reality - a call for more early determination provisions
Hypothesis: Tribunals generally have the power to make early determinations, but are reluctant to do so because of due process paranoia  Recent years have seen many arbitral institutions update their rules to include procedural mechanisms aimed at increasing efficiency in arbitral proceedings. Efficiency is often held out as one of the advantages of arbitration over litigation, both in terms of time and cost, but effective procedural tools are essential to ensuring that arbitration maintains this ‘edge’ over litigation.  One such tool is an 'early determination' pro­ced­ure. Based on our own experience, and in light of the considerable focus in recent years on the issue of ‘due process paranoia’, we hypothesised that tribunals generally have the power to dispose of cases at an early stage, but are reluctant to do so. In order to investigate our hypothesis, we analysed the rules of 29 arbitral institutions from around the world. Our results are below, together with our views on what the results of that analysis mean for arbitration’s promises and aspirations as to efficiency. Results: the rules of the majority of arbitral institutions do not explicitly empower tribunals to make early determinations of an entire claim or defence An ‘early determination’ or ‘early dismissal’ procedure allows a tribunal to reject unmeritorious claims or defences at an early stage of proceedings, avoiding the wasted time and cost of pursuing and defending matters that need never see a final hearing. Given the widespread adoption of summary judgment procedures in court processes, particularly in common law jurisdictions, the inclusion of early determination procedures in arbitral rules is crucial if arbitration is going to go toe-to-toe with litigation in the efficiency stakes. Only 9 of the 29 arbitral institutions we considered have an express early determination provision in their rules allowing for summary disposal of an entire claim or defence.[1] Our analysis shows that the rules of these 29 institutions broadly fall into four categories: 
Deciphering dispute values in arbitration - A call for consistent reporting
Hypothesis: The total sum in dispute spiked and settled in line with arbitration caseloads[1]  In our first report exploring arbitration topics as part of our ‘data driven disputes’ campaign, we saw arbitration caseloads spike in 2020 and 2021 due to the COVID pandemic and other international geopolitical issues. The numbers have since settled back down. In this third report, we look at whether the Total Sum in Dispute[2] followed the same trajectory as the Arbitration Caseloads, with a spike in 2020 and 2021 before stabilising. We also considered whether the average value of an arbitration dispute (the Mean and Median Sum in Dispute) changed in response to those same global dynamics and, if so – how? Our starting point was to consider whether fire-fighting the effects of COVID-19 and the financial crisis may have forced many small and medium sized-en­ter­prises (with correspondingly small and medium-sized disputes) not to pursue arbitrations when they otherwise might have done. This could have artificially inflated the Mean Sum in Dispute for arbitrations registered in 2020-2021, given that only large and more financially stable organisations would be in a position to bring their typically (albeit not always) larger disputes. In the process of testing our hypotheses, we discovered that there was a noticeable lack of data on disputes values published by arbitral institutions, and where data is available, there is a significant lack of uniformity in terms of what is reported and how it is reported. In our view, this is a cause of concern, as institutions should be striving for transparency and accountability, not only as an end in itself, but also to helps arbitration users when selecting an institution to administer their disputes. Greater transparency would also allow institutions to consider global trends and identify how best to position themselves and their services. Research and methodology In order to conduct our analysis, we carried out desk research and qualitative interviews: Trajectory of total sum in dispute vs arbitration caseloads – regional disparities As noted above, there was a significant discrepancy in the amount of data that was publicly available in relation to the Total Sum in Dispute as compared with the institutions’ caseloads. However, we did observe that despite the overall increase in arbitration caseloads globally, the Total Sum in Dispute did not follow the same trend globally, only in Europe. As shown in the graph below, most of the major European institutions saw the Total Sum in Dispute increase (for instance, the ICC’s Total Sum in Dispute increased from USD 37bn in 2017 to USD 101bn in 2022). However, in the APAC region, the statistics show an overall decline in the Total Sum in Dispute over the past five years (with the exception of CIETAC, which consistently saw growth over the last five years from USD 10 bn to USD 17 bn, save for a slight dip in 2020). Given that APAC was the best performing market in terms of the number of arbitrations filed in 2022, one might have expected a correlating increase in the Total Sum in Dispute. However, as shown on the graph below, both SIAC and HKIAC, the two major institutions in APAC, did not see any significant growth in the Total Sum in Dispute overall. The SIAC did see a spike in 2019-2020, and this may be due to increased cases as a result of the COVID-19 pandemic, which has since stabilised. Unfortunately, there is not enough data available from institutions from other regions to discern a trend in terms of dispute values outside of Europe and Asia. The ICDR-AAA publishes data on Total Sum in Dispute and this has been fluctuating, at USD 8.2bn in 2018, dipping to USD 4.8bn in 2019, increasing to USD 6.1bn in 2020, and dipping to USD 4.2 bn in 2022. Largest players In terms of arbitral institutions with the highest dispute values, ICC is at the top of the table with a Total Sum in Dispute of US$ 37 bn – US$ 112 bn over the period 2017 to 2022, followed by CIETAC with US$10.11 bn – 17.85 bn over the period 2017 to 2022. ICDR, DIS, HKIAC, and SIAC make up the next category of institutions, with Total Dispute Values falling in the US$ 4bn – US$ 8bn range over the period 2017 to 2022. Most other institutions have a Total Sum in Dispute Value of US$ 2bn or less, such as SCC, VIAC and SAC. Impact on SMEs and average dispute values Only five of the institutions that we analysed report the Mean Sum in Dispute, while only two report the Median Sum in Dispute. Due to the scarcity of data on the Mean or Median Sum in Dispute, we were not able effectively to test our second hypothesis on whether average dispute values did indeed spike alongside caseload numbers in 2020/2021 and then settle back down. However, in APAC, the fact that (a) there was an increase in case numbers and (b) the Total Sum in Dispute declined suggests that the Mean Sum in Dispute in APAC fell, contrary to what we hypothesised. Scarce and inconsistent data on dispute values As is evident from our analysis above, our ability to identify trends around dispute values has been limited by the fact that many arbitral institutions do not publish data on dispute values, and where such data is publicly available, there is a lack of consistency across institutions in how this data is reported. Most institutions that publish data on dispute values provide the Total Sum in Dispute[3], a handful provide a breakdown of those administered by the institution[4] and some include counterclaim amounts[5]. Some institutions only report on the Median Sum in Dispute[6], while others indicate the percentage of cases within different ranges[7]. Only five of the institutions we analysed report the Mean Sum in Dispute[8], whereas only two report the Median Sum in Dispute[9]. Bodies such as the International Federation for Commercial Arbitration Institutions[10] are exploring the possibility of institutions harmonising the way they arrive at and report their statistics. Such standardisation would certainly help users, though it does not yet seem to have gained much traction with the arbitral institutions. A call to action for arbitral institutions The broader conclusion from our analysis is that institutions should strive towards greater transparency and consistency in reporting the Total, Mean, and Median Sum in Dispute, as well as the general spread of cases.
Risk Essentials: Dispute resolution clauses - more care, less abandon
Poorly drafted dispute provisions not only fail the primary objective of directing disputes into the agreed forum but can also add a layer of dispute before the real dispute resolution starts. In this...
How sector preferences shape international arbitration
Hypothesis: The Energy and Construction sectors dominate in international arbitration On the international arbitration stage, the energy and construction sectors have long held the spotlight. With their complex, high-value contracts and cross-border transactions, which often involve a political element, disputes in these sectors are well suited to adjudication by a neutral, international arbitral tribunal.  In this second report in a series of data sheets exploring arbitration topics as part of our ‘data driven disputes’ campaign we take another deep dive into the data to investigate whether our hypothesis was the whole “sector story”. Adopting a global perspective, we analysed institutional data to identify which sectors have experienced a surge in arbitrations, which have fallen by the wayside, and we queried whether specific regions have become arbitration hotspots for particular sectors. We also spoke to the institutions about which sectors they anticipate to be areas of growth in the coming years.    Research and methodology In order to conduct this analysis, CMS carried out desk research and qualitative interviews: Results The data clearly showed that, whilst energy and construction remain dominant in the arbitration world, that dominance is not universal. Indeed, other specific sectors are increasingly prominent for certain arbitral providers. For example, whereas construction takes the top spot in Dubai, the ICDR in the U.S. has seen an increase in technology arbitrations. Meanwhile HKIAC is enjoying a FinTech boom and Japan is seeing a gaming surge.  Various factors are likely to be behind this. The regions in which the institutions are based are likely to be relevant; construction has seen significant growth in the Middle East due to tourism and foreign investment, while in contrast the gaming industry is thriving in Japan, home to some of the biggest names in the sector.  Reputation and track record remain key. Banking and finance parties, for example, continue to look to the LCIA in light of its history of dealing with high-value and complex financial disputes. Customised rules also play a part; the ICDR’s tech­no­logy-spe­cif­ic clauses allow tech companies to tailor their arbitration process to suit the subject matter of their contract.  Looking to the future, there appears to be a cross-regional expectation that green energy cases will account for a significant number of disputes in due course. As we determined in our first report, there is clear scope for more specialist centres to emerge, with these centres coexisting with the more generalist institutions. We consider below how the existing institutions may try to adapt and evolve as a result.  Technology and AI Several of the institutions that we spoke to highlighted Technology as a sector that had experienced a recent uptick in cases and one that they expected to experience continued growth. The Vienna International Arbitration Centre (VIAC), for example, has seen ‘Technology’ knock ‘Commercial Contracts’ from the top spot, with 29.7% of cases relating to the Technology sector in 2022. Similarly, Technology is now number one for the International Centre for Dispute Resolution (ICDR) in the U.S. Interestingly, despite the extent to which the benefits, risks and regulation of artificial intelligence (AI) is currently dominating the public discourse, only one institution (the Korean Commercial Arbitration Board (KCAB) International) specifically highlighted AI to us as an area in which they anticipated seeing future disputes. KCAB International described the work they are doing internally to ensure they are up-to-speed on the developments for their consumers. We consider the approach of the institutions to AI in more detail in a future edition of this report.  
International arbitration trends - What the data says
CMS conducted a data-driven project to assess whether the number of arbitrations is decreasing and if there are trends that can be identified in this type of dispute resolution. We are publishing our findings in a series of six data-driven articles.
Arbitration is surviving and thriving - don't believe everything you hear
Hypothesis: The number of arbitrations is decreasing In recent years the arbitration press and conference circuit has spent much time reflecting on whether there has been a reduction in the number of arbitrations being filed. If true, such a trend would have major implications for commercial parties who would usually choose to include arbitration agreements in their contracts – as well as dispute resolution lawyers across the board – and would raise the question as to what forum parties are choosing instead. They may choose different institutions or seats of arbitration or may even move away from arbitration as their preferred forum for dispute resolution. The importance of this possibility led to CMS conducting its own investigation to test if this hypothesis is true. Are there trends? Has there been a decline in the numbers of arbitrations being filed? This is the first in a series of data sheets to explore this, and related topics, in detail. Research and methodology In order to conduct this analysis, CMS carried out desk research and qualitative in­ter­views:Al­though in recent years some institutions reported slight dips in the numbers of registered arbitrations, these have not been hugely significant and do not appear to indicate any long-term trends. The falls generally have been attributed to numbers settling back after spikes in 2020 and 2021 related to the COVID pandemic and other international geopolitical issues. Overall case numbers reached a peak of 8,200 cases in 2020 across our sample of institutions, falling back slightly to 7,800 in 2022, still comfortably above the 6,600 seen in 2017. 
Technology Transformation - Life Sciences & Healthcare
The Life Sciences and Healthcare Sector is highly tech­no­logy-driv­en and an increasingly dynamic approach is taken when adopting busi­ness-crit­ic­al technologies. This sector’s above-average uptake in technology is reflected in its prioritisation of measures against IT failure. However, the sector is often underprepared for technology risks, with many businesses still not having processes in place to manage key risks despite current and future concerns around disputes arising from this area. This report is a deep dive into data first produced for the report Technology Transformation: Managing Risks in a Changing Landscape. This saw over 500 people surveyed from multiple industries across the world. Here we look in detail at the 75 respondents from the Life Sciences and Healthcare sector, and their perspectives on the risks associated with busi­ness-crit­ic­al technologies, including emerging technologies. Download the Technology Transformation Life Sciences and Healthcare report now to read about:Drivers of technology adoption in the Life Sciences and Healthcare sectorNew risks emerging and traditional barriers to risk man­age­ment­Cur­rent technology risks in the Life Sciences and Healthcare sectorFuture risks, including IP concerns and AIPreferred approaches to technology dispute resolution for the Life Sciences and Healthcare sector
Life Sciences are reaping the reward of digital advances but IP and contract...
Digital transformation in life sciences is creating opportunities to counter healthcare’s most intractable problems from treating rare diseases to accelerating diagnostics and reducing treatment backlogs. But technological advances are outstripping legislative and regulatory frameworks giving rise to a landscape strewn with issues over data, privacy and IP, the recent CMS Global Life Sciences & Healthcare Forum 2022 heard.“Tech­no­logy change obviously brings with it risks in implementation and new uses of technology and new regulation and legislation brings new risk,” Jeremy Mash, partner at CMS London, told delegates. AI is a potent force in life sciences with machine learning and patient data opening up new opportunities to revolutionise healthcare and relieve systems bogged down by laborious processes and shrinking budgets. The advances are welcomed across life sciences and digital has been enshrined in most nation’s health system planning but some fundamental principles such as who owns or is responsible for patient data, new routes to treatments and the consequences of mistakes have yet to be fully tested.“There are situations where you can see that evolving into risk and legal problems,” added Jeremy. “There is increasing use of legislation in the space and there is concern about where it is going to lead. There are a lot of data issues about quite what the ‘black box’ is doing and you can see people starting to raise concerns about how their data is being used.“There is also a lot talk about who is liable if that AI does not work. Is it the person who implemented it or the person designed it?”CMS examined the emerging issues in its Technology Transformation report, which surveyed 510 senior counsel and risk managers across sectors and discovered a range of preparedness and safeguards. It identified that IP issues represent 65% of expected future technology disputes, observed Jane Hollywood, partner at CMS London and patent attorney. She said the existing risk management systems for identifying, analysing, reviewing, mitigating and monitoring IP risk may need stiff­en­ing.“It's one thing to have contractual obligations and training for your people governing how you protect your IP and not misuse third party IP,” she told the Forum, in Brussels. “But it's quite another to ensure that your procedures remain adequate while you're operating in a world of machine learning algorithms and AI facilitated decision making.”She added: “The IP system does not evolve as quickly as technology advances and therefore we can have challenges obtaining protection for new technologies. We've seen this very much with AI and digital health technologies where patent protection can be difficult to get.”She said that identifying ownership and capturing developments in a fast-moving sector where collaboration and joint ventures are common can also generate disputes.“Big Pharma is increasingly partnering with digital health companies for drug discovery and patient engagement and clinical trial automation and, again, there's a lack of clarity about who owns the data that's generated from these partnerships so this is also likely to lead to disputes in the future,” said Jane. To read the full survey, visit Technology Transformation report.
Global LSHC Forum 2022
Uncertain times, an evolving legal framework: managing risks and ensuring social responsibility in the life sciences & healthcare sector
Global Life Sciences & Healthcare Forum 2022
Uncertain times, an evolving legal framework: managing risks and ensuring social responsibility in the life sciences & healthcare sector