Common Data Access

About Common Data Access Limited

From 1994 – 2022, Common Data Access Limited (better known as CDA) delivered shared data services to the UK offshore oil and gas industry, focussing on collaborative services to share well and seismic data, and supporting the professionalisation and recognition of data managers within the industry as a whole.

CDA’s UKOilandGasData system was operated as an industry-led, member-funded collaborative system to store and share well and seismic data, and to enable offshore licensees to meet their regulatory reporting requirements. During its time as an industry-operated system, it is estimated that CDA’s collaborative systems have created savings for the offshore energy industry in excess of £300 million.

CDA also played an active role in supporting the UK fishing industry, by ensuring that locations of offshore oil and gas infrastructure were collated, maintained, and shared via the FishSafe scheme, operated by the Fisheries Legacy Trust Fund, with a view to avoiding fishing tackle becoming entangled with oilfield equipment, and the hazards that entails.

The UKOilandGasData system and the extensive industry-provided well, seismic and geospatial data collection held within became the foundation of the UK National Data Repository, which was launched in March 2019, and operated until June 2021 by CDA on behalf of the North Sea Transition Authority.

The agreement to operate the NDR came to an end in June 2021, with operations transferring to Osokey Limited. Since then, CDA’s activities in supporting data and digital professions within the offshore energy industry have transferred fully into Offshore Energies UK, which now provides a range of forums and groups for IT, Digital, Cyber, and Data professionals.

 A range of digital and legal shared services are also offered by OEUK’s LOGIC subsidiary, which operates on industry’s behalf on a not-for-profit basis.

In June 2022, CDA transitioned to become a dormant subsidiary within the OEUK group. For more information about the history of CDA as a company, and the challenges and benefits of delivering cross-industry collaborations, please continue to read below, or email [email protected].


The origins of CDA can be traced back to a meeting in late 1992 between Amoco and BP in Glasgow. The ideas arrived at independently by Harold Haralson and George Chisholm of Amoco were very similar to those that had emerged from an internal BP review completed earlier that same year by Alan Clark and Cliff Baister. Both companies saw the potential of significant cost savings for industry in sharing subsurface data.

The initial meeting acted as the catalyst for other companies to become involved and led directly to CDA’s creation. Stewart Robinson (retired) was involved from the outset, crucially giving the regulator’s blessing and his personal support and energy. After their meeting, the four instigators from Amoco and BP invited data managers from all operators to a meeting in May 1993 at Amoco’s Hanger Lane offices in West London. George Chisholm chaired the meeting and some 20 companies attended. By all accounts, the meeting was a ‘stormy event’ yet some common themes emerged despite obvious conflicting interests and it was agreed to hold a second meeting at BP in Aberdeen with Alan Clark in the chair.

The first industry meeting caught the imagination of John Redfern and Rob Podolski of Amerada Hess and prompted them to take action. Together they drafted a business proposal which they tabled at the meeting at BP in Aberdeen. They made a short presentation and announced their intention to issue a Request for Information (RFI) for a shared digital well log database. Some dozen companies gave their support to the idea.

Considerable work ensued throughout the remainder of 1993 as meetings alternated between Amoco in London and BP in Aberdeen to progress the RFI and to build consensus to a critical mass. Sandra Miles-Taylor, Brian Lucken, Isobel Emslie, Duncan McKay and others joined John Redfern and Rob Podolski to complete the RFI. Stewart Robinson, John Redfern and Alan Clark visited IBM and the NPD in Norway to learn about the fledgling DISKOS initiative which was starting about the same time.


The Common Industry Data Access Initiative (CIDAI) was created in January 1994.  Eventually, 36 other companies joined the initiative and Hamish Wilson and Alan Smith of Paras (now ceased trading) were engaged to work with the many CIDAI volunteers to convert the RFI responses into a Request for Proposal (RFP). 

The majority of CDA work in these early days was done by volunteers. Amerada Hess and Amoco were driving the initiative, however, smaller committees from other companies worked on specific issues such as standards, entitlements and the RFP tender evaluation.  Stewart Robinson, John Redfern and Isobel Emslie went to Canada to meet QC Data (later acquired by IHS Energy) and to gain more insight into their online LogAxxsesservice in Calgary in the autumn of 1994.

In parallel, participating companies set about establishing the legal entity, Common Data Access Limited, as the contract vehicle from the CIDAI side and to gain their companies’ material support.  This was a very difficult task and the early challenges to success were considerable:

  • to make a robust business case which suited all oil companies, whether small non-operators or large majors;
  • to devise a fair and equitable funding model;
  • to develop a security model that would not compromise members’ own IT arrangements;
  • to negotiate a Shareholders’ Agreement and Memorandum and Articles of Association for CDA acceptable to all;
  • to convince oil company management that CDA was a worthwhile project.

John Redfern led the charge through the red tape and business issues culminating in a signing ceremony attended by the Minister for Energy at the time (Tim Eggar) and company Managing Directors.  Consensus was fast-tracked and Common Data Access Limited was established in March 1995 with John Redfern as the first Chairman.

Operations Finally Start

After competitive tender, a contract to operate the digital wells logs system was awarded to QC Data from Calgary the same month. Paras was engaged to provide administrative support to the company volunteers now meeting monthly as the CDA Board of Directors.

QC Data was required to go live with the operational system on 20th March 1996 and the project brought several data management challenges unprecedented in the UK establishing and implementing common data management standards including

  • well names and company names
  • identifying and maintaining well and well data ownership
  • determining how to structure and manage entitlement to data
  • establishing CDA within individual member company business processes.

It is thanks to the individuals mentioned above and to many others who made important contributions (unfortunately too many to name) that CDA was created.

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