TGS ASA

Investor Presentation • Sep 10, 2025

S E P T E M B E R 1 0 , 2 0 2 5

Pareto Securities Energy Conference

K R I S T I A N J O H A N S E N - CEO

Legal Notice

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TGS At a Glance

Source: Company information

Notes: ¹ TGS is listed on the Oslo Stock Exchange (OSE) and included in the OBX index. Tradable at OTCQX in New York. Market cap data as of August 21, 2025, USD/NOK: 0.1025; ² June 30, 2025; ³ Based on quarterly dividend of USD 0.155 annualized and share price as of 5 September 2025; ⁴ June 30, 2025; ⁵ June 30, 2025; ⁶ June, 30 2025 net debt of \$479m and June 30, 2025 POC LTM EBITDA of \$957m; ⁷ Net-debt excluding leases.

TGS – The Only Fully Integrated Geophysical Company

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2018

TGS' integrated model enables business opportunities in all markets and optimizes asset utilization

Synergy Realization and Strong Cost Discipline...

• Gross operating cost reduced by USD 150 million relative to 2024 (pro-forma)
• Expected 2025 gross operating cost reduced USD 100 million during 1H
• Major cost savings from
  • Synergies from PGS merger
  • Optimizing asset utilization
  • Leveraging integrated model

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…Safeguarding EBITDA in a Challenging Environment

• Despite significant drop in H1 2025 revenue, EBITDA was maintained due to reduced costs
• Strong Q1 followed by weaker Q2 caused by uncertain macro environment in combination with non-recurring operational challenges
• USD 89 million of cash flow to equity funding dividend payments of USD 61 million

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Strong Balance Sheet in a Cyclical Industry

• TGS focuses on a strong balance to maintain flexibility throughout the cycle
• TGS' leverage ratio is significantly below peers
• Target net debt in the range of USD 250–350 million
  • USD 479 million end Q2 2025

¹Net debt excluding lease liabilities / LTM EBITDA

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²Average leverage ratio of Subsea 7, Baker Hughes, Seadrill, Valaris, SLB, Halliburton and DOF.

Outlook

Oil & Gas Remaining the Key Energy Source for Decades

ExxonMobil Global Outlook 2025

• Demand for oil projected to grow to ~105 mb/d by 2050
  • Up 5% from ~100 mb/d in 2024
• Demand for gas projected to grow to ~500 BCFD in 2050
  • Up 20% from current levels
• Oil and gas will remain an important part of future energy mix
  • Projected at 54% of total in 2050

Source: ExxonMobil Global Outlook 2025.

About Time to Explore

• Continuous low exploration spending negatively impacts reserve replacement ratios
• RRR average below 1 over the last decade
• In a slower than expected energy transition scenario oil demand will increase more than expected in 2030 and beyond
• If oil and gas constitute a larger share of future energy mix it is about time to explore more

10 Source graphs and bullets: Melius Research LLC

subsurface on seismic images we get now is quite remarkable and that derisks exploration drilling."

to light up the rock in a way we never could before, has made a difference."

Investors Value Oil Discoveries

12 ¹bp reported better than expected Q2 2025 results the day after they announced the Bumerange discovery, bp's largest in 25 years.

• Several oil discoveries announced during August
• Positive share price reactions for oil companies announcing discoveries
• High quality seismic data needed for exploration success and production optimization

Summary

• TGS uniquely positioned as the only fully integrated geophysical company
  • More than 60% of all modern multi-client data globally
  • Leading assets and technologies across the value chain
  • Strong balance sheet and continuous cost focus
• More exploration needed to meet future energy demand
• Several recent exploration successes in TGS' core basins

Thank you

Energy Starts With Us

Appendix

Illustrative 2025 Cash Outflow excl. Net Working Capital Movements

Revenue requirement for 2025 cash flow potential

3D Streamer Contract Tenders

• Low value of outstanding streamer bids
• Stable streamer margins last 24 months
• Integrated business model enables TGS to establish long-term agreements and bid selectively

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OBN Market Development

• 2025 OBN mid to deepwater market revenues expected to be in line with 2023
  • 2025 market revenues likely to decline 10-15% vs. 2024
  • Some larger projects postponed to 2026
• Commenced tendering process for 2026 summer season
• More fragmented supply side variable degree of discipline