Kosmos Awards Subsea 7 Contract for Tiberius Tieback in Gulf of Mexico

Kosmos Energy has let a contract valued at $50-150 million to Subsea 7 SA for the Tiberius project in the US Gulf of Mexico. The award advances a development that carries a final investment decision, an already drilled well, and a first-oil target of end third-quarter 2028.

Kosmos Energy Gulf of Mexico Operations LLC, a unit of Kosmos Energy, signed the deal. The scope covers fabrication, transportation, and installation of a 14-km steel catenary riser (a pipe rising from the seabed to a floating host in a gentle curve) and a wet-insulated flowline to the Lucius Spar. Subsea 7 will also install an umbilical — the control and supply line running from host to seabed — together with subsea controls.

Where does Tiberius sit?

The project lies in Keathley Canyon lease block 964, roughly 400 km south of New Orleans, in about 2,283 m of water. Water depth of that order places Tiberius firmly in the deepwater Gulf of Mexico, tying back to existing Lucius infrastructure rather than requiring a new floating host.

The reservoir position and host arrangement define the economics: a single-tieback design to a spar already on station keeps the subsea hardware bill within the $50-150 million band Subsea 7 has booked for the contract.

What has been sanctioned?

License partners reached a final investment decision on the Phase 1A development this year. Phase 1A includes completion of an already drilled well, which shortens the path to production relative to a greenfield schedule.

Long-lead items — components with extended manufacturing times such as trees and controls hardware — have been secured, removing a common source of startup slippage.

The timeline breaks down as follows:

• Project management and engineering: start in the coming months, per Subsea 7
• Offshore installation activities: expected to begin in 2028
• First oil: expected by end of third-quarter 2028

Subsea 7 values the contract at $50-150 million. The company did not state a breakdown between the riser, flowline, and umbilical scopes.

Who holds the license?

Kosmos is operator of Tiberius with a 33.34% interest. The company reached that position through a farmout (a partial transfer of equity) alongside partner Occidental Petroleum to Navitas Petroleum US LLC earlier this year.

The interest structure matters for the schedule. Three-company license groups require alignment on completion design and installation sequencing before offshore work begins, and the FID already in place signals that alignment on Phase 1A.

What to watch

The critical path now runs through engineering execution ahead of the 2028 offshore campaign, with first oil by end third-quarter 2028 as the dated milestone. Watch for installation vessel assignment and any revision to the completion schedule for the drilled well, the two items most likely to move the startup date.