Open Intertest (OI)

Our Brands

Traders of  Environmental Progress

STX Group is a global environmental commodities trader offering physical and financial solutions across compliance and voluntary systems for energy, fuels, gas and carbon markets.

Transforming Climate Challenges into Business Progress

STRIVE is the advisory arm of STX Group, helping companies meet climate targets through high-impact strategies and cost-efficient decarbonization pathways.

Emissions trading in safe hands

Vertis, a MiFID II trading firm, supports companies in navigating through carbon compliance schemes, including different EU Emissions Trading Systems, CBAM and CORSIA, in a cost-effective way

Moving oil to perfect use

Marine Olie is a trader in vegetable oils and fats, delivering tailored feedstock solutions for biofuels, biomass and animal feed, with in-house blending, lab and storage capabilities.

Refers to the total number of outstanding contracts in a market that have not yet been closed, exercised, or delivered. It’s a measure of how many active positions exist in futures, options, or similar derivatives. A fall in open interest usually indicates traders are closing positions, while a rise suggests new positions are being opened.

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