One Rock Capital Partners to Sell Majority Stake in Island Energy Services in Strategic Growth Transaction
One Rock Capital Partners, LLC, a prominent value-driven private equity firm known for its operational focus, has announced a significant development involving one of its portfolio companies, Island Energy Services, LLC (IES). The firm revealed that IES has entered into a definitive agreement to sell a majority equity stake to a newly created joint venture between First Reserve, a global private equity investment firm dedicated to the energy sector, and investment funds managed by affiliates of Fortress Investment Group, a diversified global investment manager.
Despite the sale of the majority stake, One Rock will maintain an ongoing financial interest in IES through an affiliated entity, signaling confidence in the company’s long-term growth potential and strategic trajectory. Although the financial terms of the transaction remain confidential, the deal is slated for closure in the third quarter of 2025, pending customary regulatory approvals and closing conditions.
A Deep-Rooted Energy Infrastructure in Hawaii
Island Energy Services operates as a critical component of Hawaii’s energy landscape, overseeing an expansive, fully integrated network for importing, storing, and distributing fuel across the islands. As an energy logistics powerhouse, IES plays a pivotal role in ensuring fuel availability for a broad range of clients including commercial airlines, refiners, local retailers, and government agencies. These operations span the major Hawaiian Islands, representing a substantial portion of the state’s energy infrastructure backbone.
Among IES’s high-profile assets is its Texaco®-branded retail network, comprising 50 service stations and convenience stores located at key traffic points throughout the state. This retail footprint is recognized for its convenient locations and strong brand presence, and it serves as a vital access point for everyday consumers. The retail stations are also an integral part of IES’s customer engagement strategy, providing essential services and fueling convenience to both residents and visitors in one of the most geographically isolated markets in the United States.
Strategic Transformation Under One Rock’s Stewardship
The transaction marks the culmination of a highly transformative period for IES under the guidance and strategic oversight of One Rock Capital. Since acquiring the company, One Rock has been instrumental in reshaping IES’s operational model and market positioning.
“During our ownership period, IES has established itself as one of Hawaii’s most efficient fuel logistics operators,” said Michael Koike, Partner at One Rock Capital Partners. “Under the leadership of CEO Jon Mauer, the Company has undergone a significant evolution — shifting from traditional refinery operations to a modern logistics-driven platform. This includes securing critical supply chain contracts, revitalizing the retail experience, and investing in renewable energy capabilities that align with Hawaii’s ambitious energy transition goals.”
One of the most notable aspects of this transformation was IES’s departure from refinery operations, which had historically defined the company’s profile. Instead, IES pivoted toward becoming a fuel transportation and distribution specialist — a move that required both capital investment and operational realignment. This strategic repositioning not only enhanced the company’s efficiency but also positioned it as a vital contributor to Hawaii’s clean energy transition, which aims to reduce the state’s reliance on fossil fuels and increase the use of renewable energy sources.
Thomas Lamothe, Principal at One Rock, echoed the sentiment: “Working closely with our Operating Partners, IES has grown significantly. The management team’s focus and dedication to operational excellence have positioned IES to serve Hawaii’s energy needs more effectively than ever before. This next phase of growth with First Reserve and Fortress represents a natural progression in the company’s evolution.”
First Reserve and Fortress: Strategic Partners for the Next Phase
The decision to partner with First Reserve and Fortress is seen as a calculated move to inject new energy into IES’s next phase of development. First Reserve brings deep expertise in energy infrastructure, with a long history of investing in companies across the traditional and renewable energy sectors. Fortress, for its part, contributes robust investment and asset management experience across a wide range of industries, with a proven track record of supporting operationally complex businesses.
Both firms are expected to play a key role in supporting IES’s continued expansion, particularly in its efforts to diversify fuel offerings, invest in sustainable energy infrastructure, and enhance logistics capabilities across the state. Their involvement is expected to accelerate IES’s plans to develop renewable fuels infrastructure and expand its strategic footprint within the Pacific energy market.
IES CEO Jon Mauer: A Vision for Hawaii’s Energy Future
Jon Mauer, CEO of Island Energy Services, will continue to lead the company through this transition and beyond. He praised the collaborative efforts with One Rock and expressed optimism about the company’s future with its new investment partners.
“Under One Rock’s ownership, we have transformed our business into one of Hawaii’s premier energy infrastructure platforms and executed multiple growth initiatives that have created significant long-term value,” said Mauer. “We are proud of the progress we’ve made and look forward to our next chapter of growth alongside First Reserve, Fortress, and One Rock. Our mission remains centered on supporting Hawaii’s energy reliability, resiliency, and sustainability.”
Mauer’s leadership has been central to IES’s evolution over the past few years, particularly during times of global fuel supply volatility and increasing regulatory pressure to adopt cleaner energy solutions. Under his guidance, the company has not only maintained fuel reliability for the state but has also made inroads into green energy — a critical area of investment as Hawaii seeks to become carbon neutral by 2045, one of the most aggressive climate goals in the U.S.
Financial and Legal Advisors
In this transaction, Evercore and Nomura Securities International, Inc. served as exclusive financial advisors to Island Energy Services, leveraging their expertise in M&A and energy sector transactions to help structure the deal. Latham & Watkins LLP, a leading international law firm, provided legal counsel, ensuring that the transaction adhered to all relevant regulatory and contractual obligations.
