TULSA, Okla., Jan. 21, 2013 (GLOBE NEWSWIRE) -- SemGroup® Corporation (NYSE:SEMG) (SemGroup) and Rose Rock Midstream, L.P. (NYSE:RRMS) will attend the US Capital Midstream Corporate Access Day in Houston, Texas, on Tuesday, January 29, 2013.

SemGroup and Rose Rock Midstream Chief Executive Officer Norm Szydlowski and Chief Financial Officer Bob Fitzgerald will conduct one-on-one meetings with members of the investment community.

The presentation materials used during the conference will be accessible on the SemGroup website at www.semgroupcorp.com and the Rose Rock Midstream website at www.rrmidstream.com on Tuesday, January 29, 2013.

About SemGroup

Based in Tulsa, Oklahoma, SemGroup® Corporation is a publicly traded midstream service company providing the energy industry the means to move products from the wellhead to the wholesale marketplace. SemGroup provides diversified services for end users and consumers of crude oil, natural gas, natural gas liquids, refined products and asphalt. Services include purchasing, selling, processing, transporting, terminalling and storing energy.

The SemGroup Corporation logo is available at http://www.globenewswire.com/newsroom/prs/?pkgid=14815

SemGroup®, is a registered trademark of SemGroup Corporation.

About Rose Rock Midstream

Rose Rock Midstream, L.P. (NYSE:RRMS) is a growth-oriented Delaware limited partnership formed by SemGroup® Corporation (NYSE:SEMG) to own, operate, develop and acquire a diversified portfolio of midstream energy assets. Rose Rock Midstream provides crude oil gathering, transportation, storage and marketing services. Headquartered in Tulsa, OK, Rose Rock Midstream has operations in six states with the majority of its assets strategically located in or connected to the Cushing, Oklahoma crude oil marketing hub.

The Rose Rock Midstream logo is available at http://www.globenewswire.com/newsroom/prs/?pkgid=16626

CONTACT: Investor Relations:
         Alisa Perkins, 918-524-8081
         investor.relations@semgroupcorp.com
         roserockir@rrmidstream.com

         Media:
         Liz Barclay, 918-524-8158
         lbarclay@semgroupcorp.com
         lbarclay@rrmidstream.com
Source: SemGroup Corporation; Rose Rock Midstream, L.P.
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