Gary Oliver
Senior Clerk
+44 (0) 207 822 7325
Diya Sen Gupta KC specialises in complex and significant employment litigation in the areas of employee competition, business protection, whistleblowing and discrimination. She is primarily instructed in cases which are commercially and reputationally significant.
Diya has been shortlisted for the Senior Counsel of the Year award (International Employment Lawyer Awards 2024) and has previously been shortlisted for the Employment Silk of the Year award (Legal 500 Bar Awards 2024 and Legal 500 Bar Awards 2023).
Diya's recent reported cases include:
Diya is highly rated by both leading independent legal directories, the Legal 500 and Chambers & Partners. Recent comments includes:
Previous comments include:
Prior to taking silk, Diya was named Employment Junior of the Year (Chambers UK Bar Awards 2016) and was shortlisted for the Employment Junior of the Year award (Chambers UK Bar Awards 2015). She was the only employment barrister featured in an article in Legal Week as one of ten ‘Future stars at the Bar’, which said that ‘Diya Sen Gupta is a favourite of City firms…pragmatic, tough, passionate and fiendishly bright'.
Diya was Chair of the Employment Law Bar Association (2019-2021), having previously served as Vice Chair, Secretary and Treasurer.
Diya Sen Gupta KC specialises in complex and significant employment litigation including in the areas of employee competition, business protection, whistleblowing and discrimination.
Diya is instructed in cases which typically involve difficult issues of law, are commercially and reputationally significant, and of substantial financial value, such as team move cases.
Diya is recognised as a leading silk in employment by both Chambers UK and Legal 500. She is "a superb advocate and a pleasure to work with" (Legal 500 UK 2020). "Diya is a fantastic all-rounder who is very bright and gets involved with the team" (Chambers UK 2020).
“Diya knows employment law inside out. She is insightful and strategic in her approach, with a pragmatic and approachable air. She impresses in court, and delivers amazing results - a genuine superhero of the barrister world.”
Legal 500, 2025
“Diya is superb and is often our first pick when we need a silk for complex, high-value disputes.”
Chambers and Partners, 2025
“Diya has an enviable ability to balance both an incredibly sharp legal ability with proper commercial understanding.”
Chambers and Partners, 2025
“Diya is superb. Her attention to detail is exceptional.”
Chambers and Partners, 2025
“Her presence in court is exceptional and she is clear and persuasive in all of her submissions.”
Chambers and Partners, 2023
“Diya is extremely client-friendly, incredibly calm under pressure and a superb advocate who gets straight to the point.”
Chambers and Partners, 2023
“Diya is fiercely intelligent, hands-on and a real team player. She works as part of the team on the full range of litigation rather than being a barrister who just concentrates on the hearing. Diya is also a formidable advocate – she has a calm, inquisiti”
Legal 500, 2023
“She is incredibly bright, has great attention to detail and is strategic.”
Chambers and Partners, 2022
“She is an excellent advocate”
Chambers and Partners, 2022
“Very client friendly – a real go-to star.”
Legal 500, 2022
“Incredibly intelligent and phenomenally hard-working.”
Chambers and Partners, 2021
“She's absolutely sharp as a razor and great with clients.”
Chambers and Partners, 2021
“A real team player, who is incredibly thorough and detail focused – incredibly effective!”
Legal 500, 2021
“Diya is pragmatic, thorough, commercial and very client-friendly.”
Chambers and Partners, 2020
“A fantastic all-rounder who is very bright and gets involved with the team.”
Chambers and Partners, 2020
“A superb advocate and a pleasure to work with. Her written work is a particular highlight”
Legal 500, 2019
“An effective and incisive advocate”
Chambers and Partners, 2019
“She has great attention to detail.”
Chambers and Partners, 2019
“Incredibly hard-working.”
Chambers and Partners, 2019
“Super bright”
Chambers and Partners, 2019
“Always prepared and will work tirelessly to get the best results.”
Chambers and Partners, 2018
“Her understanding of employment law is second to none.”
Legal 500, 2018
“She can very quickly grasp the issues and the importance of the case to the client - she instils confidence in the client and is able to establish a rapport with them quickly”
Chambers and Partners, 2017
“An exceptional advocate.”
Legal 500, 2017
“A persuasive advocate, who quickly puts clients at ease and wins their confidence”
Legal 500, 2016
“She is highly meticulous and strategic in her approach, and has total command of the courtroom.”
Legal 500, 2015
Acting for fintech company defending sexual harassment claim by former contract worker.
Diya acted for the insurance broker defendants in an employee competition dispute which included claims for breach of non-solicitation covenant and misuse of confidential information. The matter settled shortly before the expedited trial.
Whistleblowing claim in which Diya successfully resisted claimant's application for interim relief.
Diya successfully acted for the appellant in this appeal before the EAT which concerned the application of the burden of proof in a discrimination case.
Acting for a digital media company in a team move case
Diya acted for Tim Sarnoff in the Employment Appeal Tribunal (EAT) in this appeal which concerned the extent of the Employment Tribunal’s power to make a disclosure order against a person outside Great Britain. The EAT dismissed Mr Sarnoff’s appeal but granted him permission to appeal to the Court of Appeal.
Acting for a fintech company in a confidential information case.
Diya acted for the appellant in this appeal to the EAT concerning the issue whether a claim which had been withdrawn but not dismissed could be revived.
Diya successfully defended the respondents in this high-profile sex discrimination case.
Diya successfully represented the Bank in this appeal to the EAT against the ET's original dismissal of the claim and its subsequent dismissal of the claimant's application for reconsideration.
Appeal before the Court of Appeal concerning the ET's power to order disclosure against an individual outside the jurisdiction, in the context of a harassment claim against Harvey Weinstein.
Advising energy company in relation to breach of confidence by a former employee who claimed to be a whistleblower.
Diya successfully obtained strike out of the claimant's claims in a case which concerned the meaning of "applicant" in section 39 of the Equality Act 2010.
Diya was instructed by a media company to conduct an investigation into bullying allegations against the Executive Chairman.
Diya was instructed by a set of Chambers to conduct an investigation in relation to sexual harassment allegations against a barrister.
Diya successfully represented the respondents before the Court of Appeal in this complex disability discrimination case which concerned the correct approach to direct disability discrimination claims; the distinction between direct disability discrimination and discrimination arising from disability; and whether the concept of "indissociability" can apply to disability discrimination.
Diya is acting in a claim relating to sexual harassment allegations against Harvey Weinstein.
Application for interim injunctive relief against a senior employee to enforce restrictive covenants.
Diya was instructed to conduct a complex investigation into misconduct allegations against employees at a university.
Diya was instructed by a law firm to conduct an investigation into sexual harassment allegations against a partner.
Diya was instructed to provide expert evidence on English employment law in Lisbon Labour Court.
Diya acted for a law firm defending a maternity discrimination claim.
Diya successfully acted for Ofgem in this complex appeal concerning the tribunal's disclosure powers in the context of a very high profile whistleblowing claim. The EAT considered the scope of its duty to interpret domestic legislation in confirming with the European Convention on Human Rights. The matter settled prior to the hearing before the Court of Appeal.
Diya acted for three Cantor Fitzgerald employees seeking a stay of English High Court proceedings against them on the basis that any such proceedings should be brought in the State of New York.
Diya acted for Alliance Surgical at the High Court trial of its factually and legally complex claim against its former CEO for Database Right infringement.
Diya acted for the Managing Director of Private Banking who claimed he was unfairly dismissed after raising whistleblowing concerns about alleged weaknesses in the bank's controls and systems for dealing with high-risk transactions. The case was widely reported in the financial press including by the Financial Times:
https://www.ft.com/content/427f15d6-7f8e-11e8-bc55-50daf11b720d
Diya acted for a US technology company in its LCIA arbitration claim against its former Group Managing Directors who set up a competing business in breach of non-competition covenants in a Share Purchase Agreement.
Acted for Luke Miels, a senior employee of Astrazeneca who resigned to join GlaxoSmithKline, a rival pharmaceutical company. This high-profile case involved a claim by Astrazeneca to enforce 12 months’ garden leave against Mr Miels. The proceedings were settled shortly before a speedy trial.
Diya acted for the bank in successfully defending unfair dismissal claim brought by former Foreign Exchange trader.
Acted for BGC in successfully defending claim of inducement of breach of contract. The dispute arose when an employee of ICAP resigned to join BGC, a competitor. The case has been reported and is now a leading authority on garden leave and inducement of breach of contract.
Diya represented Dyson in proceedings brought against its former chief executive.
Diya successfully defended this high profile whistleblowing claim by the former Global Head of Voice Spot at Barclays.
Diya acted pro bono for the Dalit Solidarity Network, challenging the Government's failure to make caste discrimination unlawful.
Acted for Citibank defending this claim by a former Foreign Exchange trader arising from his dismissal for sharing client confidential information in Bloomberg Chats. Diya successfully obtained a restricted reporting order preventing Citibank’s clients from being named.
Diya acted for a law firm defending a sex discrimination claim by a current senior associate complaining about her non-promotion to partner and her discretionary bonus.
Acted for a magic circle law firm in relation to a race discrimination claim by a former banking associate.
Acted for Citibank defending this claim by a former Foreign Exchange trader arising from his dismissal for sharing client confidential information in Bloomberg Chats. Diya successfully obtained a restricted reporting order preventing Citibank’s clients from being named.
Acted for a major television production company defending claims of whistleblowing, sexual harassment and victimisation by a former writer.
Diya successfully defended the Bank both in respect of the original claim but also, most recently, in relation to the reconsideration of certain aspects of the original judgment. The claim was for over £6.4 million and was brought by the former Head of Funding Structuring who alleged that his manager, Geoff Smailes, had unlawfully terminated his employment in order to take the credit for a particular trade idea. This allegation was rejected in its entirety and both the Bank and Mr Smailes were fully exonerated of all allegations made against them.
Diya successfully represented World Duty Free before the Court of Appeal in this employment status appeal under the Equality Act 2010. Diya also drafted World Duty Free’s notice of objection to Mrs Halawi’s petition to the Supreme Court. Mrs Halawi’s petition was dismissed by the Supreme Court.
Acted for Citibank defending this claim by a former Foreign Exchange trader arising from his dismissal for sharing client confidential information in Bloomberg Chats. Diya successfully obtained a restricted reporting order preventing Citibank’s clients from being named and also successfully resisted the claimant’s application for an order for reinstatement. This case has been widely reported in the press.
Acted for a magic circle law firm defending a claim of constructive dismissal by a former tax manager.
Acted for a Russian bank defending claims of sex discrimination by its former HR Director who had been made redundant.
Acted advising a former employee of a well-known contact lens company about the enforceability of restrictive covenants contained in a share purchase agreement and the merits of his claims for wrongful and unfair dismissal.
Represented a bank defending claims by a group of employees in connection with changes made to the bank’s bonus scheme.
Diya successfully represented the appellant in this indirect age discrimination appeal in the EAT.
Advised a bank in relation to a grievance process involving an employee with mental health issues (2015).
Advised a bank defending claims of disability discrimination following the claimant trader’s dismissal for gross misconduct (2015).
Advised a Jersey company specialising in intellectual property services in its claims for interim injunctions to enforce non-compete covenants against two former employees who had joined a competitor (2015).
Acted for a major financial services company defending a disability discrimination claim by a former investment adviser (2015).
Diya acted for the former international CEO of a well-known insurance brokerage, defending a claim for damages arising from an alleged team move and injunction to enforce post-termination covenants. The matter settled before a 5-week High Court trial, reportedly for £20 million.
Diya successfully represented the respondents in this complex and sensitive sexual harassment claim.
Following the highly publicised allegations of sexual harassment made against Lord Rennard, Diya was instructed by the Chief Executive of the Liberal Democrats to review the disciplinary procedures of the Liberal Democrats and to recommend any changes required. Her instruction was publicised by the then Liberal Democrat Party President, Tim Farron, on the Party’s website following the conclusion of the disciplinary process against Lord Rennard.
Diya represented the Head teacher of a school who alleged that she had been forced out as part of the Trojan Horse plot.
Represented the Bank of Tokyo and the claimant’s former managers at the trial of this complex whistleblowing and race discrimination claim which was heard over 3 weeks.
Acted for an architect who had set up a business competing with his previous employer, defending a claim for breach of contract and breach of fiduciary duty and pursuing a substantial counterclaim for bonus.
Represented a bank defending an application for an injunction to restrain the suspension of a current employee.
Diya successfully represented the transferee in this appeal concerning the construction of regulations 13 and 15 of TUPE. The EAT held TUPE does not provide a transferred employee with an independent cause of action against the transferee respondent in respect of an alleged failure by the transferee to comply with its obligation to provide information to the transferor.
Acted for the former managing director of a football club in his contract claim against the club.
Diya successfully represented the claimant at a rule 3(10) hearing in the EAT in this appeal concerning the burden of proof in whistleblowing cases.
Diya acted for FICC Market Standards Board Ltd (FMSB) and three individual named respondents in this complex whistleblowing claim. FMSB successfully resisted the claimant's application for interim relief.
Acted for Citibank defending this claim by a former Foreign Exchange trader arising from his dismissal for sharing client confidential information in Bloomberg Chats. Diya successfully obtained a restricted reporting order preventing Citibank’s clients from being named.
Acted for Citibank defending this claim by a former Foreign Exchange trader arising from his dismissal for sharing client confidential information in Bloomberg Chats. Diya successfully obtained a restricted reporting order preventing Citibank’s clients from being named.
Successfully represented QPR in defending employment claim by former Academy Football Operations Officer.
Acted for an LLP law firm in its defence of claims made by a former member of the LLP for disability discrimination, victimisation and whistleblowing detriment.
Diya acted for six individuals in this team move case which involved consideration of interim relief, enforceability of non-solicitation and non-dealing covenants, and TUPE issues. The matter settled before speedy trial.
Diya successfully represented World Duty Free in the EAT before Langstaff P in the first appellate decision on the meaning of “employment” in section 83(2) of the Equality Act 2010.
Successfully represented the Bank in defending a claim by a trader on the CDO Desk for wrongful dismissal and unfair dismissal following his involvement in wash trades.
Successfully represented the claimant at an oral permission hearing in the Court of Appeal in this appeal concerning disability discrimination principles and costs orders.
Acted for the respondent in this disability discrimination claim by an employee on long-term sickness absence which was said by him to be worth almost £5 million.
Diya successfully represented the defendant software company in defending the claimant’s appeal to the EAT against the ET’s strike out of her claim of marital status discrimination.
Diya acted for the asset management business in this 2-week High Court trial following a move by the claimant to a competitor and successfully defended the claim for £1.7 million. The judgment contains helpful analysis of the scope of the duty of fidelity and the application of the penalty doctrine to the terms of a compromise agreement and deferred remuneration plans.
Diya acted in this expedited judicial review challenge to proposed amendments to the National Minimum Wage Regulations. The basis for challenge included failure to comply with the general equality duty under the RRA 1976 and discrimination contrary to Article 45 of the TFEU, Regulation 1612/68 and Directive 2000/43/EC.
Diya represented the Equality and Human Rights Commission as intervener in the landmark “Heyday” age discrimination judicial review case which challenged the default retirement age of 65 as being unlawful under EU law.
Diya acted for the appellant in the Court of Appeal in this appeal concerning the issue whether a claim which had been withdrawn but not dismissed could be revived.
Diya has substantial experience of employee competition and business protection cases, with particular expertise in team moves.
She acts for individuals (employees, members, partners), teams, employers and LLP partnerships in relation to the various issues which arise when there is a move to a competing business, whether as a team or separately.
Diya is frequently instructed on applications for interim relief and (speedy) trials in this context.
Diya also advises on contractual and fiduciary duties, enforceability of restrictive covenants, garden leave, confidential information, wrongful termination, injunctive relief, damages claims and loss of profits claims.
Diya is often invited to speak on employee competition and team move issues, for example:
Diya's recent employee competition bulletins and articles include:
Diya is also a contributor to the leading textbook Employee Competition: Covenants, Confidentiality, and Garden Leave (2nd (2011) and 3rd (2016) editions).
“Diya is pragmatic, thorough, commercial and very client-friendly.”
Chambers and Partners, 2020
“A fantastic all-rounder who is very bright and gets involved with the team.”
Chambers and Partners, 2020
“A superb advocate and a pleasure to work with. Her written work is a particular highlight”
Legal 500, 2019
“An effective and incisive advocate”
Chambers and Partners, 2019
“She has great attention to detail.”
Chambers and Partners, 2019
“Incredibly hard-working.”
Chambers and Partners, 2019
“Super bright”
Chambers and Partners, 2019
“Always prepared and will work tirelessly to get the best results.”
Chambers and Partners, 2018
“Her understanding of employment law is second to none.”
Legal 500, 2018
“She can very quickly grasp the issues and the importance of the case to the client - she instils confidence in the client and is able to establish a rapport with them quickly”
Chambers and Partners, 2017
“An exceptional advocate.”
Legal 500, 2017
“A persuasive advocate, who quickly puts clients at ease and wins their confidence”
Legal 500, 2016
“She is highly meticulous and strategic in her approach, and has total command of the courtroom.”
Legal 500, 2015
Advised a Jersey company specialising in intellectual property services in its claims for interim injunctions to enforce non-compete covenants against two former employees who had joined a competitor (2015).
Acting for a digital media company in a team move case
Acting for a fintech company in a confidential information case.
Diya acted for the insurance broker defendants in an employee competition dispute which included claims for breach of non-solicitation covenant and misuse of confidential information. The matter settled shortly before the expedited trial.
Diya acted for three Cantor Fitzgerald employees seeking a stay of English High Court proceedings against them on the basis that any such proceedings should be brought in the State of New York.
Application for interim injunctive relief against a senior employee to enforce restrictive covenants.
Diya acted for Alliance Surgical at the High Court trial of its factually and legally complex claim against its former CEO for Database Right infringement.
Diya acted for a US technology company in its LCIA arbitration claim against its former Group Managing Directors who set up a competing business in breach of non-competition covenants in a Share Purchase Agreement.
Acted for Luke Miels, a senior employee of Astrazeneca who resigned to join GlaxoSmithKline, a rival pharmaceutical company. This high-profile case involved a claim by Astrazeneca to enforce 12 months’ garden leave against Mr Miels. The proceedings were settled shortly before a speedy trial.
Acted for BGC in successfully defending claim of inducement of breach of contract. The dispute arose when an employee of ICAP resigned to join BGC, a competitor. The case has been reported and is now a leading authority on garden leave and inducement of breach of contract.
Diya represented Dyson in proceedings brought against its former chief executive.
Diya acted for the former international CEO of a well-known insurance brokerage, defending a claim for damages arising from an alleged team move and injunction to enforce post-termination covenants. The matter settled before a 5-week High Court trial, reportedly for £20 million.
Acted advising a former employee of a well-known contact lens company about the enforceability of restrictive covenants contained in a share purchase agreement and the merits of his claims for wrongful and unfair dismissal.
Acted for an architect who had set up a business competing with his previous employer, defending a claim for breach of contract and breach of fiduciary duty and pursuing a substantial counterclaim for bonus.
Diya acted for six individuals in this team move case which involved consideration of interim relief, enforceability of non-solicitation and non-dealing covenants, and TUPE issues. The matter settled before speedy trial.
Diya acted for the asset management business in this 2-week High Court trial following a move by the claimant to a competitor and successfully defended the claim for £1.7 million. The judgment contains helpful analysis of the scope of the duty of fidelity and the application of the penalty doctrine to the terms of a compromise agreement and deferred remuneration plans.
Diya frequently advises on breach of confidence and misuse of confidential information claims, including applications for delivery up and other injunctive relief. Many of these claims settle without a hearing.
Advising energy company in relation to breach of confidence by a former employee who claimed to be a whistleblower.
Diya acted for Alliance Surgical at the High Court trial of its factually and legally complex claim against its former CEO for Database Right infringement.
Diya acted for the former international CEO of a well-known insurance brokerage, defending a claim for damages arising from an alleged team move and injunction to enforce post-termination covenants. The matter settled before a 5-week High Court trial, reportedly for £20 million.
Diya acts in a variety of high value bonus disputes.
Diya acted for three Cantor Fitzgerald employees seeking a stay of English High Court proceedings against them on the basis that any such proceedings should be brought in the State of New York.
Diya acted for a law firm defending a sex discrimination claim by a current senior associate complaining about her non-promotion to partner and her discretionary bonus.
Represented a bank defending claims by a group of employees in connection with changes made to the bank’s bonus scheme.
Acted for an architect who had set up a business competing with his previous employer, defending a claim for breach of contract and breach of fiduciary duty and pursuing a substantial counterclaim for bonus.
Diya acted for the asset management business in this 2-week High Court trial following a move by the claimant to a competitor and successfully defended the claim for £1.7 million. The judgment contains helpful analysis of the scope of the duty of fidelity and the application of the penalty doctrine to the terms of a compromise agreement and deferred remuneration plans.
Diya has a wealth of experience acting in whistleblowing claims, including very high profile matters.
Diya has successfully resisted numerous applications for interim relief.
Diya is keenly aware of the importance of the relevant regulatory context in whistleblowing claims.
“Diya is pragmatic, thorough, commercial and very client-friendly.”
Chambers and Partners, 2020
“A fantastic all-rounder who is very bright and gets involved with the team.”
Chambers and Partners, 2020
“A superb advocate and a pleasure to work with. Her written work is a particular highlight”
Legal 500, 2019
“An effective and incisive advocate”
Chambers and Partners, 2019
“She has great attention to detail.”
Chambers and Partners, 2019
“Incredibly hard-working.”
Chambers and Partners, 2019
“Super bright”
Chambers and Partners, 2019
“Always prepared and will work tirelessly to get the best results.”
Chambers and Partners, 2018
“Her understanding of employment law is second to none.”
Legal 500, 2018
“An exceptional advocate.”
Legal 500, 2017
“A persuasive advocate, who quickly puts clients at ease and wins their confidence”
Legal 500, 2016
“She is highly meticulous and strategic in her approach, and has total command of the courtroom.”
Legal 500, 2015
Advising energy company in relation to breach of confidence by a former employee who claimed to be a whistleblower.
Whistleblowing claim in which Diya successfully resisted claimant's application for interim relief.
Acted for an LLP law firm in its defence of claims made by a former member of the LLP for disability discrimination, victimisation and whistleblowing detriment.
Diya successfully acted for Ofgem in this complex appeal concerning the tribunal's disclosure powers in the context of a very high profile whistleblowing claim. The EAT considered the scope of its duty to interpret domestic legislation in confirming with the European Convention on Human Rights. The matter settled prior to the hearing before the Court of Appeal.
Diya acted for the Managing Director of Private Banking who claimed he was unfairly dismissed after raising whistleblowing concerns about alleged weaknesses in the bank's controls and systems for dealing with high-risk transactions. The case was widely reported in the financial press including by the Financial Times:
https://www.ft.com/content/427f15d6-7f8e-11e8-bc55-50daf11b720d
Diya successfully defended this high profile whistleblowing claim by the former Global Head of Voice Spot at Barclays.
Acted for a major television production company defending claims of whistleblowing, sexual harassment and victimisation by a former writer.
Diya acted for FICC Market Standards Board Ltd (FMSB) and three individual named respondents in this complex whistleblowing claim. FMSB successfully resisted the claimant's application for interim relief.
Represented the Bank of Tokyo and the claimant’s former managers at the trial of this complex whistleblowing and race discrimination claim which was heard over 3 weeks.
Diya successfully represented the claimant at a rule 3(10) hearing in the EAT in this appeal concerning the burden of proof in whistleblowing cases.
Diya has acted in numerous cases concerning employment status including Halawi v WDFG UK Ltd (t/a World Duty Free) [2015] IRLR 50 (meaning of "employment" in the Equality Act 2010) and provides advice in this developing area of the law.
Diya acted for Tim Sarnoff in the Employment Appeal Tribunal (EAT) in this appeal which concerned the extent of the Employment Tribunal’s power to make a disclosure order against a person outside Great Britain. The EAT dismissed Mr Sarnoff’s appeal but granted him permission to appeal to the Court of Appeal.
Acting for fintech company defending sexual harassment claim by former contract worker.
Diya successfully represented World Duty Free before the Court of Appeal in this employment status appeal under the Equality Act 2010. Diya also drafted World Duty Free’s notice of objection to Mrs Halawi’s petition to the Supreme Court. Mrs Halawi’s petition was dismissed by the Supreme Court.
Diya is acting in a claim relating to sexual harassment allegations against Harvey Weinstein.
Appeal before the Court of Appeal concerning the ET's power to order disclosure against an individual outside the jurisdiction, in the context of a harassment claim against Harvey Weinstein.
Acted for the former managing director of a football club in his contract claim against the club.
Diya successfully represented World Duty Free in the EAT before Langstaff P in the first appellate decision on the meaning of “employment” in section 83(2) of the Equality Act 2010.
Successfully represented the Bank in defending a claim by a trader on the CDO Desk for wrongful dismissal and unfair dismissal following his involvement in wash trades.
Diya has substantial experience of conducting highly sensitive and confidential investigations for a range of clients and in a variety of contexts.
Recent work includes investigating:
Diya is representing Frontline Migrant Health Workers Group at the Covid-19 Inquiry (Module 3: Impact on healthcare system).
“Anything Diya turns her hand to is excellent.”
Chambers and Partners, 2025
Diya was instructed to conduct a complex investigation into misconduct allegations against employees at a university.
Diya was instructed by a media company to conduct an investigation into bullying allegations against the Executive Chairman.
Diya was instructed by a law firm to conduct an investigation into sexual harassment allegations against a partner.
Diya was instructed by a set of Chambers to conduct an investigation in relation to sexual harassment allegations against a barrister.
Diya has extensive experience of acting in a wide range of discrimination claims (including age, race, religion or belief, sex, sexual harassment, sexual orientation), primarily representing employers and LLP partnerships as well as individual senior executives named as respondents.
Diya is acting in a claim relating to sexual harassment allegations against Harvey Weinstein.
Diya successfully defended the respondents in this high-profile sex discrimination case.
Diya successfully acted for the appellant in this appeal before the EAT which concerned the application of the burden of proof in a discrimination case.
Appeal before the Court of Appeal concerning the ET's power to order disclosure against an individual outside the jurisdiction, in the context of a harassment claim against Harvey Weinstein.
Diya successfully obtained strike out of the claimant's claims in a case which concerned the meaning of "applicant" in section 39 of the Equality Act 2010.
Acting for fintech company defending sexual harassment claim by former contract worker.
Diya acted for Tim Sarnoff in the Employment Appeal Tribunal (EAT) in this appeal which concerned the extent of the Employment Tribunal’s power to make a disclosure order against a person outside Great Britain. The EAT dismissed Mr Sarnoff’s appeal but granted him permission to appeal to the Court of Appeal.
Diya was instructed by a set of Chambers to conduct an investigation in relation to sexual harassment allegations against a barrister.
Acted for an LLP law firm in its defence of claims made by a former member of the LLP for disability discrimination, victimisation and whistleblowing detriment.
Diya was instructed by a law firm to conduct an investigation into sexual harassment allegations against a partner.
Diya acted for a law firm defending a maternity discrimination claim.
Diya successfully represented the respondents before the Court of Appeal in this complex disability discrimination case which concerned the correct approach to direct disability discrimination claims; the distinction between direct disability discrimination and discrimination arising from disability; and whether the concept of "indissociability" can apply to disability discrimination.
Diya acted for a law firm defending a sex discrimination claim by a current senior associate complaining about her non-promotion to partner and her discretionary bonus.
Diya acted pro bono for the Dalit Solidarity Network, challenging the Government's failure to make caste discrimination unlawful.
Acted for a major television production company defending claims of whistleblowing, sexual harassment and victimisation by a former writer.
Acted for a magic circle law firm in relation to a race discrimination claim by a former banking associate.
Acted for a Russian bank defending claims of sex discrimination by its former HR Director who had been made redundant.
Advised a bank in relation to a grievance process involving an employee with mental health issues (2015).
Diya successfully represented the appellant in this indirect age discrimination appeal in the EAT.
Advised a bank defending claims of disability discrimination following the claimant trader’s dismissal for gross misconduct (2015).
Acted for a major financial services company defending a disability discrimination claim by a former investment adviser (2015).
Diya successfully represented World Duty Free before the Court of Appeal in this employment status appeal under the Equality Act 2010. Diya also drafted World Duty Free’s notice of objection to Mrs Halawi’s petition to the Supreme Court. Mrs Halawi’s petition was dismissed by the Supreme Court.
Diya successfully represented the respondents in this complex and sensitive sexual harassment claim.
Diya represented the Head teacher of a school who alleged that she had been forced out as part of the Trojan Horse plot.
Following the highly publicised allegations of sexual harassment made against Lord Rennard, Diya was instructed by the Chief Executive of the Liberal Democrats to review the disciplinary procedures of the Liberal Democrats and to recommend any changes required. Her instruction was publicised by the then Liberal Democrat Party President, Tim Farron, on the Party’s website following the conclusion of the disciplinary process against Lord Rennard.
Represented the Bank of Tokyo and the claimant’s former managers at the trial of this complex whistleblowing and race discrimination claim which was heard over 3 weeks.
Successfully represented the claimant at an oral permission hearing in the Court of Appeal in this appeal concerning disability discrimination principles and costs orders.
Diya successfully represented World Duty Free in the EAT before Langstaff P in the first appellate decision on the meaning of “employment” in section 83(2) of the Equality Act 2010.
Acted for the respondent in this disability discrimination claim by an employee on long-term sickness absence which was said by him to be worth almost £5 million.
Diya successfully represented the defendant software company in defending the claimant’s appeal to the EAT against the ET’s strike out of her claim of marital status discrimination.
Diya represented the Equality and Human Rights Commission as intervener in the landmark “Heyday” age discrimination judicial review case which challenged the default retirement age of 65 as being unlawful under EU law.
Diya acted in this expedited judicial review challenge to proposed amendments to the National Minimum Wage Regulations. The basis for challenge included failure to comply with the general equality duty under the RRA 1976 and discrimination contrary to Article 45 of the TFEU, Regulation 1612/68 and Directive 2000/43/EC.
Diya has acted in various cases concerning TUPE issues, particularly in the appellate courts.
Acted for BGC in successfully defending claim of inducement of breach of contract. The dispute arose when an employee of ICAP resigned to join BGC, a competitor. The case has been reported and is now a leading authority on garden leave and inducement of breach of contract.
Diya successfully represented the transferee in this appeal concerning the construction of regulations 13 and 15 of TUPE. The EAT held TUPE does not provide a transferred employee with an independent cause of action against the transferee respondent in respect of an alleged failure by the transferee to comply with its obligation to provide information to the transferor.
Diya acted for six individuals in this team move case which involved consideration of interim relief, enforceability of non-solicitation and non-dealing covenants, and TUPE issues. The matter settled before speedy trial.
Diya has substantial experience of acting for members and LLP partnerships, particularly in the context of business protection.
She frequently advises on the enforceability of restrictive covenants in membership agreements, particularly in the context of financial services and law firms.
Diya is a member of the Association of Partnership Practitioners and recently gave a talk to the APP on "Team moves in the partnership context".
MA (Cantab), Law
Diya is frequently invited to speak at seminars and conferences. Recent topics include:
Between April and June 2015 Diya completed a 9-week evening Masterclass in Financial Markets at the London Stock Exchange Group.
Diya has been a member of the Blackstone Chambers Pupillage Committee, a Blackstone Chambers Equality and Diversity Officer and a Pupillage Supervisor.
Diya is a supporter of Advocate (previously the Bar Pro Bono Unit) and the COAS and ELAAS schemes and has assisted a number of individuals with their appeals in the Court of Appeal and the EAT on a pro bono basis.
Diya was a member of Devereux Chambers from 2001-2008.
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