Rosemary Onos Mba

Rosemary Onos Mba

Practice Areas

Corporate/Commercial, Energy/Natural Resources

Contact Details



12 Igbodo Street
Old G.R.A.
Port Harcourt
Rivers State

Rosemary is an experienced corporate litigator, with expertise in corporate and project finance, mergers and acquisitions, and regulatory compliance. She previously has headed a team in our Litigation/Arbitration Practice Group, and currently is the supervising senior associate in the Corporate/Commercial Practice Group and the Energy and Natural Resources Practice Group, where she provides transactional advice to international companies operating in Nigeria.

Whether representing one of our clients in complex litigation or guiding them through a strategically important transaction, Rosemary adds value through her legal experience and practical technical understanding of the construction, banking, real estate, oil and gas, and power sectors.

Some notable accomplishments for our clients by Rosemary and her team include:

  • Advising a major investor in the financing and development of a port terminal for a fertilizer project
  • Comprehensive transaction support to a bidder for the acquisition of 80% interest in a power generation company following the privatisation of the sector in Nigeria, including: regulatory issues; project structuring; take-off agreements; acquisition and merger of power assets; construction operation and management; and power purchase agreements
  • Guidance on critically important issues in a major real estate project such as: joint venture participation; public-private partnerships; asset acquisitions and dispositions; financing; construction; engineering procurement and construction contracts; environmental law; and regulatory compliance
  • Advice on key transactional issues in the natural gas industry, such as: gas supply; gas storage and plants; engineering procurement and construction; and gas sale and sharing contracts
  • Successful defence of a client against a compensation claim of more than N50 million

Professional Affiliations

  • Nigerian Bar Association


  • Nigerian Law School (B.L)
  • Ambrose Alli University (LL.B)

Rosemary enjoys travelling, singing, reading, and watching football.