Ash Costello

About Ash Ash Advises Experience Highlights Memberships Publications Supporting Documents and Templates

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Privacy, Blockchain, Digital Commerce and Technology

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About Ash

Ash is a Data-Privacy and Funds lawyer, advising on US and UK Data-Privacy laws including GDPR, CCPA, cookies and digital marketing, biometrics, artificial intelligence (AI); and on UK Funds laws specialising in property funds.

Dual-qualified in New York and England and Wales, Ash advises on the data-privacy laws of both jurisdictions, including online behavioural analytics and targeted advertising, consent management, AI privacy risks, negotiating and drafting terms and conditions including data processing agreements, and consulting on data-privacy related aspects of litigation, employment, mergers and acquisitions, and commercial, corporate and technology transactions.

Ash helps clients comply with US and UK data-privacy obligations across all aspects of their business: starting from designing and delivering compliant products and services; through implementing privacy management programmes; finishing with day-to-day compliance including website privacy notices, cookie policies, data subject and consumer rights, policies and procedures, risk assessment and management, AI incorporation, data mapping, accountability, and governance.

As a recognised authority on emerging technologies and encryption, she was appointed to the Expert Panel of the European Commission’s “European Blockchain Observatory and Platform’ (EUBOF) and was voted in as Co-Chair of the Privacy Working Group of the ‘International Association for Trusted Blockchain Applications’ (INATBA). She is also part of the Editorial Board of Citywealth’s Crypto Report.

Ash’s property funds work involves advising clients on regulated and unregulated property holding structures, launching funds and non-fund structures, day-to-day queries, co-investment and re-investment rounds, advising on loans to funds, carried interest, and drafting agreements including the IMA, LPA and administrator agreements.  Familiar with many structures including: joint-ventures, limited partnerships; Property Authorised Investment Funds; Co-Ownership Authorised Contractual Schemes; Long Term Asset Funds; UK-Real Estate Investment Trusts; Jersey Property Unit Trusts; UK Unauthorised Exempt Property Unit Trusts; Luxembourg SICAVs and FCPs; and Guernsey PCCs and ICCs.  She was included in Citywealth’s “Top 30 Irish Private Client and Family Advisors” in 2025.

Ash Advises

  • Technology providers and digital platforms
  • Financial services and payments companies
  • Funds and fund managers
  • Pharmaceutical and healthcare companies
  • Global manufacturers
  • Supply chains
  • Companies operating in regulated sectors
  • Entertainment and media companies
  • Legal and professional firms, associations and institutes

Experience Highlights

  • Global Head of Legal of a top 5 multinational Fund Administrator.   Responsible for legal strategy and legal spend, member of the operational and risk executive committees.  Oversaw the acquisition of and merger with one of our largest competitors and clients which involved: successfully migrating both entities onto a new IT platform, implementing a GDPR data-mapping exercise and privacy management programme for the combined entities as GDPR became live during the merging process.
  • Conducting GDPR and US-law data-privacy compliance audits, compiling gap-analyses, advising on remediation and the steps to compliance, implementing global and local data protection programmes. Numerous clients, including one of the world’s top 3 DAOs.
  • Advising on digital marketing and online advertising, including consent management and cookie-related litigation.
  • External-DPO assisting with day-to-day matters, risk management, bio-metric and sensitive personal data treatment, accountability and corporate governance. Clients included a multinational defence contractor.
  • Advising multinational pharmaceutical organizations and health care providers on GDPR, HIPAA and related healthcare and biometric laws; negotiating and drafting business associate agreements, privacy notices, data protection agreements, data sharing, data transfer agreements, risk management and privacy policies.
  • Advising governments and private clients on privacy-enhancing-technologies and encryption technologies such as SMPC and ZKPs and blockchain technologies, digital assets, NFTs, DAOs and smartcontracts.
  • Advising on the data protection requirements of various digital platforms and Apps dealing with healthcare, biometric data and children’s data.
  • External General Counsel for a privacy-enhancing-technology start-up, leveraging SMPC (secure multi-party computation) encryption security and a Layer 0 blockchain protocol technology stack. Advised on all legal matters, including how the privacy-enhancing-technology was considered ‘anonymous’ under data-privacy laws.
  • Advising an international supply-chain implementing ZKPs and digital identities and leveraging blockchain technology.
  • Acting for numerous funds and fund managers, assisting with: launching structures, day-to-day queries, co-investment and re-investment rounds; advising on loans to funds; carried interest; property holding structures; fund structures such as SICAV, PCC, ICC, OIEC, LTAF, JPUT, ELP, SLP; and drafting agreements including the IMA, LPA and administrator agreements.

Memberships

  • Member of the Editorial Board of Citywealth’s Crypto Report. (https://www.citywealthmag.com/publication/crypto-report/)
  • Appointed to the Expert Panel of the European Blockchain Observatory and Forum (a European Commission initiative to accelerate blockchain innovation and the development of the blockchain ecosystem within the EU and so help cement Europe’s position as a global leader in this transformative new technology.) https://www.eublockchainforum.eu/  She regularly contributes to their workshops and reports including on matters such as NFTs (non-fungible tokens), DAOs (decentralized autonomous organizations), the Blockchain Ecosystem within the EU, and Smart Contracts.
  • Co-Chair of the Privacy Working Group of the International Association of Trusted Blockchain Applications (https://inatba.org/), (2022-2023) where she explored developments regarding privacy in and for blockchain including (among others) ZKPs (zero knowledge proofs), and SMPC (secure multi-party computations).

Publications

Co-Author of reports conducted by EUBOF including:

Supporting Documents and Templates

States’ New Consumer Data Privacy Laws

US Website Notice – New Website Privacy Policy Requirements

US States’ new Consumer Data Privacy Laws

Cookies and Targeted Advertising – UK  Regulation

GDPR v US Privacy Laws

 

About Ash

Back to top

Ash is a Data-Privacy and Funds lawyer, advising on US and UK Data-Privacy laws including GDPR, CCPA, cookies and digital marketing, biometrics, artificial intelligence (AI); and on UK Funds laws specialising in property funds.

Dual-qualified in New York and England and Wales, Ash advises on the data-privacy laws of both jurisdictions, including online behavioural analytics and targeted advertising, consent management, AI privacy risks, negotiating and drafting terms and conditions including data processing agreements, and consulting on data-privacy related aspects of litigation, employment, mergers and acquisitions, and commercial, corporate and technology transactions.

Ash helps clients comply with US and UK data-privacy obligations across all aspects of their business: starting from designing and delivering compliant products and services; through implementing privacy management programmes; finishing with day-to-day compliance including website privacy notices, cookie policies, data subject and consumer rights, policies and procedures, risk assessment and management, AI incorporation, data mapping, accountability, and governance.

As a recognised authority on emerging technologies and encryption, she was appointed to the Expert Panel of the European Commission’s “European Blockchain Observatory and Platform’ (EUBOF) and was voted in as Co-Chair of the Privacy Working Group of the ‘International Association for Trusted Blockchain Applications’ (INATBA). She is also part of the Editorial Board of Citywealth’s Crypto Report.

Ash’s property funds work involves advising clients on regulated and unregulated property holding structures, launching funds and non-fund structures, day-to-day queries, co-investment and re-investment rounds, advising on loans to funds, carried interest, and drafting agreements including the IMA, LPA and administrator agreements.  Familiar with many structures including: joint-ventures, limited partnerships; Property Authorised Investment Funds; Co-Ownership Authorised Contractual Schemes; Long Term Asset Funds; UK-Real Estate Investment Trusts; Jersey Property Unit Trusts; UK Unauthorised Exempt Property Unit Trusts; Luxembourg SICAVs and FCPs; and Guernsey PCCs and ICCs.  She was included in Citywealth’s “Top 30 Irish Private Client and Family Advisors” in 2025.

Ash Advises

Back to top
  • Technology providers and digital platforms
  • Financial services and payments companies
  • Funds and fund managers
  • Pharmaceutical and healthcare companies
  • Global manufacturers
  • Supply chains
  • Companies operating in regulated sectors
  • Entertainment and media companies
  • Legal and professional firms, associations and institutes

Experience Highlights

Back to top
  • Global Head of Legal of a top 5 multinational Fund Administrator.   Responsible for legal strategy and legal spend, member of the operational and risk executive committees.  Oversaw the acquisition of and merger with one of our largest competitors and clients which involved: successfully migrating both entities onto a new IT platform, implementing a GDPR data-mapping exercise and privacy management programme for the combined entities as GDPR became live during the merging process.
  • Conducting GDPR and US-law data-privacy compliance audits, compiling gap-analyses, advising on remediation and the steps to compliance, implementing global and local data protection programmes. Numerous clients, including one of the world’s top 3 DAOs.
  • Advising on digital marketing and online advertising, including consent management and cookie-related litigation.
  • External-DPO assisting with day-to-day matters, risk management, bio-metric and sensitive personal data treatment, accountability and corporate governance. Clients included a multinational defence contractor.
  • Advising multinational pharmaceutical organizations and health care providers on GDPR, HIPAA and related healthcare and biometric laws; negotiating and drafting business associate agreements, privacy notices, data protection agreements, data sharing, data transfer agreements, risk management and privacy policies.
  • Advising governments and private clients on privacy-enhancing-technologies and encryption technologies such as SMPC and ZKPs and blockchain technologies, digital assets, NFTs, DAOs and smartcontracts.
  • Advising on the data protection requirements of various digital platforms and Apps dealing with healthcare, biometric data and children’s data.
  • External General Counsel for a privacy-enhancing-technology start-up, leveraging SMPC (secure multi-party computation) encryption security and a Layer 0 blockchain protocol technology stack. Advised on all legal matters, including how the privacy-enhancing-technology was considered ‘anonymous’ under data-privacy laws.
  • Advising an international supply-chain implementing ZKPs and digital identities and leveraging blockchain technology.
  • Acting for numerous funds and fund managers, assisting with: launching structures, day-to-day queries, co-investment and re-investment rounds; advising on loans to funds; carried interest; property holding structures; fund structures such as SICAV, PCC, ICC, OIEC, LTAF, JPUT, ELP, SLP; and drafting agreements including the IMA, LPA and administrator agreements.

Memberships

Back to top
  • Member of the Editorial Board of Citywealth’s Crypto Report. (https://www.citywealthmag.com/publication/crypto-report/)
  • Appointed to the Expert Panel of the European Blockchain Observatory and Forum (a European Commission initiative to accelerate blockchain innovation and the development of the blockchain ecosystem within the EU and so help cement Europe’s position as a global leader in this transformative new technology.) https://www.eublockchainforum.eu/  She regularly contributes to their workshops and reports including on matters such as NFTs (non-fungible tokens), DAOs (decentralized autonomous organizations), the Blockchain Ecosystem within the EU, and Smart Contracts.
  • Co-Chair of the Privacy Working Group of the International Association of Trusted Blockchain Applications (https://inatba.org/), (2022-2023) where she explored developments regarding privacy in and for blockchain including (among others) ZKPs (zero knowledge proofs), and SMPC (secure multi-party computations).

Publications

Back to top

Co-Author of reports conducted by EUBOF including:

Supporting Documents and Templates

Back to top

States’ New Consumer Data Privacy Laws

US Website Notice – New Website Privacy Policy Requirements

US States’ new Consumer Data Privacy Laws

Cookies and Targeted Advertising – UK  Regulation

GDPR v US Privacy Laws

 

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