SemGroup Corporation and Rose Rock Midstream, L.P. Announce Timing of Third Quarter 2013 Earnings Conference Call and Webcast

SemGroup Corporation and Rose Rock Midstream, L.P. Announce Timing of Third
Quarter 2013 Earnings Conference Call and Webcast

TULSA, Okla., Oct. 11, 2013 (GLOBE NEWSWIRE) -- SemGroup^® Corporation
(NYSE:SEMG) and Rose Rock Midstream^®, L.P. (NYSE:RRMS) today announced plans
to release third quarter 2013 results after the market closes on Monday,
November 11, 2013.

Rose Rock Midstream,
L.P.

A joint conference call for investors will be held at 11 AM Eastern on
Tuesday, November 12, 2013 to discuss third quarter results for both SemGroup
and Rose Rock Midstream. Hosting the call will be Norm Szydlowski, president
and chief executive officer, and Bob Fitzgerald, senior vice president and
chief financial officer. A presentation of the results will be posted before
the conference call on SemGroup's Investor Relations website at
ir.semgroupcorp.com and Rose Rock Midstream's Investor Relations website at
ir.rrmidstream.com.

What:   SemGroup Corporation and Rose Rock Midstream third quarter 2013
         earnings conference call and webcast
When:   11:00 AM Eastern, November 12, 2013
Where:  1) Phone conference call
                * U.S. callers - 877.359.3652, pass code 78050867
                * International callers - 720.545.0014, pass code 78050867
       2) Log on to the webcast at ir.semgroupcorp.com
       3) Log on to the webcast at ir.rrmidstream.com

If you are unable to participate in the conference call or webcast, a replay
will be available on both websites for a year following the call on the
Calendar of Events-Past Events page.

About SemGroup

Based in Tulsa, OK, SemGroup^® Corporation (NYSE:SEMG) 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.

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.
Headquartered in Tulsa, OK, Rose Rock Midstream provides crude oil gathering,
transportation, storage and marketing services with the majority of its assets
strategically located in or connected to the Cushing, Oklahoma crude oil
marketing hub.

CONTACT: Investor Relations:
         Mary Catherine Ward
         SemGroup - 918-524-8081
         Rose Rock Midstream - 918-524-7711
         investor.relations@semgroupcorp.com
         roserockir@rrmidstream.com
        
         Media:
         Kiley Roberson
         918-524-8594
         kroberson@semgroupcorp.com
         kroberson@rrmidstream.com

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