• Trusted
    Commercial and legal consulting for the
    upstream and midstream oil and gas industry
  • Commercial
    and legal

    Expanding beyond our core area we can now
    supply legal resource for our clients.

  • Beyond


We are the largest commercial consultancy working the UK upstream and midstream sectors. We can provide experienced and professional resource on flexible terms with the size and capability to provide continuity of service for whatever our clients need.

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Uniquely, we can also supply legal support. Using known faces who are available to work in-house or remotely at competitive rates.
This allows Sigma to offer a full negotiation and drafting service ensuring continuity and efficiency.

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We offer the "What to negotiate" courses covering the life of an asset from development through to decommissioning, and also the "How to negotiatie" course. We hold open courses and we prepare bespoke training in-house.

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Examples of our work

  • Maximising Economic Recovery

    We employ a collaborative approach to maximise economic value, using integrative negotiation
    tactics to optimise our client's position within a win-win outcome for the venture.
    We use best practice including adherence to the Commercial Code of Practice and the Infrastructure
    Code of Practice.

  • Hub optimisation

    We are working with a number of clients to update the commercial framework for producing
    hubs. This can lead to novel and flexible commercial arrangements that optimise the economics
    for both host and users derisking the remaining field life of the assets.
    This not only fulfils the obligations of MER(UK) but can give owners the comfort they need to invest
    in the assets to defer COP and maximise economic recovery.

  • Developments

    We are currently working on a number of developments, from some of the largest projects
    in Northern Europe through to challenging single well subsea tie-backs.
    We have extensive knowledge of the UKCS from Southern North Sea gas fields, through to
    Northern North Sea mature asset, the West of Shetlands frontier and heavy oil fields.

  • Decommissioning

    We work closely with other disciplines on all stages of decommissioning. From late field life
    optimisation, leases and handback, decommissioning security and the negotiation of DSAs, through COP
    preparation and application to, uniquely, the commercial aspects of the decommissioning project itself.
    Through our participation in an unrivalled number of negotiations, we know the areas of contention
    and employ a choice of strategies to overcome potential deadlocks to ensure a safe,smooth decommissioning project.

  • Due Diligence

    With our extensive working knowledge of all the major producing areas and infrastructure
    in the UKCS we work extensively with oil companies, financial houses and legal teams to
    prepare or review datarooms.
    As well as ensuring clients fully understand the commercial framework of an asset we indentify the
    risks and opportunities that can have a major influence on the asset value.

  • Expert Witness

    Sigma regularly provides expert witness services during dispute resolution processes and Court
    Leveraging our 450 man-years of experience we offer unparalleled depth of knowledge and support for
    clients, using industry-renowned consultants to provide expert opinion on our multiple areas of expertise.