SemGroup Signs Letter of Intent for $75 Million Equity Transaction with Carlyle/Riverstone

Tulsa, OK - SemGroup, L.P. announced today the execution of a letter of intent for a $75 million equity transaction with the Carlyle/Riverstone Global Energy and Power Fund II, L.P. Under terms of the proposed agreement, Carlyle/Riverstone will provide SemGroup $75 million in exchange for an approximately 30 percent interest in the privately held midstream energy company. The transaction is expected to close in the first quarter 2005.

"We are very excited about the opportunity to work with Carlyle/Riverstone and believe that our partnership will build upon SemGroup's financial and operating success. Carlyle/Riverstone is known as one of the premier private equity players in the energy and power sectors. The transaction will provide SemGroup with a strategic partner that offers a distinct combination of investment and industry professionals who have highly successful track records," Tom Kivisto, SemGroup president and chief executive officer, said.

The proposed equity transaction is the second announced by SemGroup during 2004. In April, Ritchie Capital Management, LLC, a multi-strategy hedge fund group based in Chicago with more than $1.4 billion in assets under management, bought the equity position previously owned by Energy Spectrum Partners of Dallas, Texas. Ritchie Capital owns a 25 percent equity position with SemGroup's management team owning 31 percent.

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