Riken Corporation

Company Profile




Sanbancho Tokyu Bldg., 3F, 8-1 Sanbancho, Chiyoda-ku, Tokyo, 102-8202 Japan

Business Overview

-A major supplier of piston rings in Japan. According to the Company, it owns a 50% share in Japan and 20% share in the global market.

-Sales of automotive and industrial machinery components were JPY 74.4 billion (in the fiscal year ended March 2018), accounting for 84.9% of the total sales.

ーIn its mid-term management plan "Plan 2020", the Company aims to achieve sales exceeding JPY 140 billion in fiscal year 2020.

In 2018, the Company considers the expansion of businesses other than piston rings. It formed an alliance with Tanaka Seimitsu Kogyo Co., Ltd.


-Listed on the first section of the Tokyo Stock Exchange. (As of Mar. 31, 2018)
Name or Company Name Investment Ratio (%)
Mizuho Bank Ltd. 4.95
Northern Trust Co. (AVFC) RE NV101 4.05
Nippon Life Insurance Company 3.86
Hitachi Metals Trading, Ltd. 3.63
Japan Trustee Services Bank, Ltd. (Trust Account) 3.60
The Master Trust Bank of Japan, Ltd. (Trust Account) 3.30
The Daishi Bank, Ltd. 3.26
State Street London Care of State Street Bank and Trust,
Boston SSBTC A/C UK London Branch Clients - United Kingdom
Sumitomo Mitsui Trust Bank, Limited. 2.66
The Bank of Tokyo-Mitsubishi UFJ, Ltd. 2.60
Total 34.81


Piston rings

Engine parts
-Valves seats
-Valve lifters
-Valve bridges
-Valve spring retainers
-Aluminum valve spring retainers
-Expansion chambers
-Rocker arms

Transmission parts
-Seal rings
-Differential cases
-Differential carriers
-Pinion shafts

Drive and chassis parts
-Steering knuckles
-Damper forks
-Brake calipers
-Pressure plates
-Lower arms

Other automotive parts
-Vanes for air compressors
-Shoes and shoe discs for air conditioning systems
-Vanes for power steering systems
-Sliders for power steering systems


Nov. 1927 Rikagaku Kogyo was established. This company was the first to start manufacturing practical rings in Japan.
Dec. 1949 Reestablished as Riken Kashiwazaki Piston Ring (Headquarters at 3-5 Nihonbashi, Chuo-ku), capitalized at 20 million yen.
May, 1952 Listed on the Tokyo Stock Exchange.
Oct. 1979 Corporate name changed to RIKEN Corporation.
Oct. 1998 Received the TPM first-class prize for continuing excellence
Aug. 1999 Provided technical assistance to DANA-ALBARUS (Brazil) for piston rings for VW Brazil
May, 2000 Signed a memorandum of understanding with Dana (USA) for a global tie-up in the piston ring business
Mar. 2001 RIKEN's piston ring manufacturing facilities in Kashiwazaki, Japan and Kumagaya, Japan received ISO14000 certificates.
Feb. 2003 Established the Jakarta representative office as a subordinate organization under the Asian sales team of the overseas sales division.
Jan. 2004 Established Riken Automobile Parts (Wuhan) Co., Ltd. in Hubei, China to manufacture and sell piston rings etc. in China.
Oct. 2004 The Company's piston ring division and the precision machinery component division at the Kumagaya plant received ISO/TS16949 certification in October 2004. (The Company's main domestic and overseas subsidiaries received ISO/TS16949 certification around October 2004.)
June, 2007 The Company and MAHLE GmbH signed a memorandum of understanding under which they will form a global business alliance in the areas of piston rings, camshafts, and other products.
Jan. 2008 The Company sold all shares it owned in Riken of Korea Inc. As a result, the Korean company will be removed from the Group's consolidated statements from fiscal year 2008.
June, 2010 Formed an Overseas Committee designed to promote business strategies outside Japan based on a cross-section of operations.
Aug. 2012 Established Riken Mexico, S.A. DE C.V. as a production plant to supply automotive and industrial machinery parts to North, South, and Central America; in Aguascalientes.
Aug. 2014 Sold entire 100 percent stake of Riken Espana, S.A., and removed it from its consolidated financial statements.
Aug. 2014 Moved its headquarters to Sanbancho, Chiyoda-ku, Tokyo.
Oct. 2014 Jointly with Amtek India Limited, the Company established Amtek Riken Casting Private Limited in Rajasthan, India to manufacture and sell automotive castings.
Apr. 2015 Signed an MOU with KS Kolbenschmidt (based in Germany) that covers global sales, engineering, and development of power cylinder systems that includes pistons and piston rings.
Spun off the sealing ring business of Riken Automobile Parts (Wuhan) Co., Ltd., establishing it as Riken Sealing Parts (Wuhan) Co., Ltd., in order to strengthen the sealing-ring business in China.
Oct. 2015 Established Riken Sales and Trading (Thailand) Co., Ltd. in Bangkok, Thailand, to strengthen sales of piston rings in Asia.
Apr. 2017 Formed a business alliance of the camshaft business with Brother Precision Ind. Co., Ltd. and set up Riken Brother Precision Industry Corporation in Chiryu City, Aichi Pref.

Supplemental Information 1

Joint Venture Contract

(As of Mar. 31, 2016)
Partner Country Name of Joint Venture Share of investment Contract date Remarks
Ho Tsung Yuan and others Taiwan Taiwan Riken Ind. Co., Ltd. 50% Dec. 15, 1966 Manufacturing and sales of automotive parts
Siam Motors Co., Ltd. Thailand Siam Riken Ind. Co., Ltd. 49% Dec. 20, 2015 Manufacturing and sales of automotive parts
1. P.T. Pakarti Yoga
2. Meiwa Corp.
Indonesia P.T. Pakarti Riken Indonesia 40% Aug. 22, 1975 Manufacturing and sales of joint and automotive parts
Mahle Engine Components
USA, Inc..
USA Allied Ring Corporation 50% June 13, 1989 Manufacturing and sales of piston rings

CK Metals Limited

Japan CK Riken JV Co., Ltd. 40% Dec. 14, 2011 Manufacturing and sales of piping equipment

KSPG China

China Riken Automobile Parts (Wuhan) Co., Ltd. 70% Dec. 08, 2015 Manufacturing and sales of automotive parts

>>>Business report FY ended Mar. 31, 2008
>>>Business report FY ended Mar. 31, 2009
>>>Business report FY ended Mar. 31, 2010
>>>Business report FY ended Mar. 31, 2011
>>>Business report FY ended Mar. 31, 2012
>>>Business report FY ended Mar. 31, 2013
>>>Business report FY ended Mar. 31, 2014
>>>Business report FY ended Mar. 31, 2015
>>>Business report FY ended Mar. 31, 2016
>>>Business report FY ended Mar. 31, 2017

Archives of Past Exhibits

Note: A figure in brackets ( ) indicates a loss