Projects

Mahato & Sampang PSCs
Indonesia

Mahato: Horizon effective interests ~6.4% through Cue
Sampang: Horizon effective participating interests ~8.6% through Cue

Indonesia

Mahato and Sampang production sharing contracts

Horizon’s Indonesian portfolio is held through Cue Energy and comprises interests in the Mahato and Sampang production sharing contracts.

Mahato PSC

Asset Overview

Horizon Interest: Approximately 8.6% effective participating interest through Cue¹

Cue holds an 11.25% participating interest in the Mahato PSC in Central Sumatra, operated by Texcal. Production is sourced primarily from the PB field’s Bekasap reservoir. Development activity includes approved infill drilling, with the Operator also progressing the OPL-3 development plan and preparations for the GA-1 exploration well.

Location
Onshore Central Sumatra, Indonesia

Asset
Mahato production sharing contract, or PSC. Production is sourced primarily from the PB field’s Bekasap reservoir

Recent Highlights from FY2026

Development activity includes approved infill drilling, with the Operator also progressing the OPL-3 development plan and preparations for the GA-1 exploration well

Background

The PB field was discovered in late 2019 and began commercial oil production in early 2021. It lies within the Central Sumatra Basin, which also contains the Minas and Duri oil fields

Sampang PSC

Asset Overview

Horizon Interest: Approximately 8.6% effective participating interest through Cue¹

Cue holds a 15% participating interest in the Sampang PSC, operated by Medco, which contains the producing Oyong and Wortel gas fields. Production continues from both fields while the Joint Venture progresses compression facilities and evaluates opportunities to optimise recovery from existing wells. Cue has advised the Joint Venture that it does not intend to participate beyond the current PSC expiry in December 2027.

Location
Offshore East Java, Indonesia

Asset
Sampang PSC, including the producing Oyong and Wortel gas fields

Recent Highlights from FY2026

Production continues from both fields while the Joint Venture progresses compression facilities and evaluates opportunities to optimise recovery from existing wells
Cue has advised the Joint Venture that it does not intend to participate beyond the current PSC expiry in December 2027

Background

The Sampang PSC lies in the Madura Strait, East Java. Oyong gas production began in 2009 and Wortel followed in 2012. Gas travels through a subsea pipeline to the Grati processing plant and is supplied to PT Indonesia Power for electricity generation

1. Effective interests include Horizon’s proportionate interest through its 57.03% controlling shareholding in Cue Energy Resources Limited where applicable. The underlying licence interests remain legally held by Cue.