# One Stone Energy Partners, L.P.
One Stone Energy Partners, L.P. is a [Cayman Islands](https://www.edgepedia.org/cayman-islands) limited partnership, based at 730 [Fifth Avenue](https://www.edgepedia.org/fifth-avenue) in New York City, that invests in natural resources with a primary focus on oil and gas, and which raised $109 million from investors in 2012.[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) The fund's manager is One Stone Partners L.L.C., a Delaware limited liability company, and its general partner is One Stone Energy Partners GP, L.L.C.[2](https://www.9at.com/Adviser/801-100473) Its one publicly disclosed investment is a $23.5 million preferred-share purchase in Magellan Petroleum closed in May 2013.[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm)
| Fact | Detail |
|---|---|
| Structure | Cayman Islands limited partnership; adviser One Stone Partners L.L.C.; general partner One Stone Energy Partners GP, L.L.C.[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) • [2](https://www.9at.com/Adviser/801-100473) |
| Headquarters | 730 Fifth Avenue, New York, NY 10019[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) |
| Principals | Robert Israel and Vadim Gluzman (managing members), Edmund Hajim (general partner member)[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) • [3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm) |
| 2012 fundraise | $109,000,000 sold of a $150,000,000 offering; first sale February 8, 2012; 26 investors; $1,000,000 minimum[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) |
| Disclosed investment | $23.5 million for 19,239,734 Series A Convertible Preferred shares of Magellan Petroleum, closed May 17, 2013[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm) |
| Adviser AUM | Approximately $264,123,668 as of December 31, 2023, all discretionary (unverified; carried only by a directory summary of the Form ADV)[2](https://www.9at.com/Adviser/801-100473) |
## What One Stone Energy Partners is
The fund is the investment vehicle; the operating firm behind it is One Stone Partners L.L.C., which provides advisory services to One Stone Energy Partners, L.P. and to other privately pooled investment vehicles.[2](https://www.9at.com/Adviser/801-100473) According to Magellan Petroleum's May 2013 closing press release, One Stone is a New York-based private equity firm focused on investments in the oil and gas industry.[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm) The same release describes the firm's strategy as identifying "underdeveloped assets" in the natural resources sector, with geographic areas of interest in North and South America, Europe, and [West Africa](https://www.edgepedia.org/west-africa).[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm)
## Founding and the 2012 fundraise
The fund's capital raise is documented in a Rule 506 Form D filed with the SEC on February 16, 2012. The filing reports total offering amount of $150,000,000, with $109,000,000 sold as of the first sale date of February 8, 2012, leaving $41,000,000 unsold, and a minimum investment of $1,000,000 accepted from outside investors.[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) The offering had 26 investors, and the filing states that no sales commissions or selling remuneration would be paid.[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) The Form D does not identify the limited partners.
Robert Israel signed the filing as Manager on February 16, 2012.[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt)
## People
Robert Israel and Vadim Gluzman are the managing members of One Stone Energy Partners.[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm) The Form D identifies Israel and Gluzman as Promoter and Managing Member of the General Partner, and Edmund Hajim as Promoter and Member of the General Partner.[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) The adviser's Form ADV summary states that Israel, Gluzman, and Hajim are the principal owners of the firm.[2](https://www.9at.com/Adviser/801-100473)
Before One Stone, Israel was a partner at Compass Advisers LLP and headed the energy department of Schroder & Co. from 1991 to 2000. Gluzman was a vice president of OAO LUKOIL and President of Lukoil Americas Holding.[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm) When the Magellan investment closed in May 2013, Israel and Gluzman joined Magellan Petroleum's board of directors.[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm)
## Investments: the Magellan Petroleum deal
The fund's one publicly disclosed investment is in Magellan Petroleum Corporation. On May 17, 2013, Magellan received $23.5 million in exchange for 19,239,734 shares of Series A Convertible Preferred Stock issued to One Stone. The conversion price was $1.22 per share, a 20% premium to the ten-day volume-weighted average price, and the transaction involved no advisory fees or warrants.[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm) No other portfolio transactions for the fund appear in the checked record.
## By the numbers
The fund raised $109 million of a $150 million target in February 2012.[1](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt) The only disclosed deployment is the $23.5 million Magellan preferred investment, roughly a fifth of the amount sold in the offering.[3](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm) The adviser's Form ADV summary reports regulatory assets under management of approximately $264.1 million as of December 31, 2023, all managed on a discretionary basis, across the fund and other pooled vehicles (unverified; carried only by a directory summary).[2](https://www.9at.com/Adviser/801-100473)
## Status through 2026
The adviser's Form ADV summary reports assets under management as of December 31, 2023 (unverified; carried only by a directory summary).[2](https://www.9at.com/Adviser/801-100473) No source in the record reports an exit, shutdown, renaming, or acquisition of the fund or its manager.[2](https://www.9at.com/Adviser/801-100473)
## References
1. [SEC Form D filing: One Stone Energy Partners, L.P. (CIK 0001541776, filed 2012-02-16)](https://www.sec.gov/Archives/edgar/data/1541776/0001541776-12-000002.txt)
2. [One Stone Partners L.L.C. Form ADV summary (SEC adviser 801-100473)](https://www.9at.com/Adviser/801-100473)
3. [Magellan Petroleum press release: closing of Series A investment by One Stone (May 20, 2013, SEC EX-99.1)](https://www.sec.gov/Archives/edgar/data/61398/000006139813000027/a2013-05x20seriesapressrel.htm)
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*Topic: Encyclopedia › Technology and the built world › Energy technology › Energy economics, security, and crises*
*Initially written Sep 17, 2026 · Edited: Oct 11, 2026; Oct 15, 2026*
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