S white
on blue
Flag
Company
Country
Thos. Smailes & Son UK
Standard Oil Company of New York US
Skou International A/S, Copenhagen
Denmark
Arthur Sewall & Company US
N.V. Scheldt Towage Co., S.A., Antwerp

blue flag, white "S".

("N.V." in Dutch is "S.A." in French = limited liability company)
Belgium
Shinwa Kaiun Kaisha Ltd Japan
Samer & Co. Shipping Ltd
Italy
Slobodna Plovidba - Sibenik
Croatia
Sven Salén A/B Sweden
New Zealand Sea Transport Ltd. New Zealand
Max Sötje Tankschiffahrt GmbH
 Germany
Sealift Inc. US
Reederei Wilhelm Schepers K.G., Haren/Ems
Germany
Sicula Oceanica
Italy
Great Yarmouth Shipping Co. Ltd.
UK
Suffolk Marine Ltd., Lowestoft
UK
Seatrans Group Norway
Sardegna Regionale Marittima S.p.A. Italy
Slite Cement & Kalk
Sweden
Anders Smith
Sweden
Sogestran France
Sprague Steamship Co. US
C.H. Sorensen & Sonner, Arendal
Norway
State Line UK
Heinrich Schütt Germany
J.H.T. Schupp Germany
Surecruit Latvia
Surecruit Russia
John Stewart & Co. Shipping
UK
Stoffers BV
Netherlands
Shamrock Shipping Company, Limited, Larne Harbour
UK
British Steel plc., London
UK
Sardegna Regionale Marittima S.p.A. Italy