RS Technologies Co., Ltd.
RS Technologies Co., Ltd. is registered in Japan. The on-file registration data for this profile carries Japanese corporate number 2011001145054, assigned 14 January 2022 and shown as Active on the National Tax Agency’s Corporate Number Publication Site, with a registered location in Minato Ward, Tokyo. Verification of that specific corporate number resolves instead to a company written in katakana as 株式会社ＲＳテクノロジーズ, registered at 2F, 2-2-15 Hamamatsucho, Minato Ward, Tokyo — a different registered address from the company operating the website supplied for this profile, https://www.rs-tec.jp/. That website, and its own official corporate profile page, identify a separate Japanese legal entity written with Roman-letter “Technologies”, 株式会社RS Technologies (RS Technologies Co., Ltd.), Japanese corporate number 3010701024500, established 10 December 2010 and headquartered at 1-47-1 Oi, Shinagawa Ward, Tokyo. Because both entities render identically as “RS Technologies Co., Ltd.” in English, this profile cannot fully reconcile the on-file registration number and 2022 incorporation date with the company operating the supplied website; this conflict should be independently resolved before relying on the registration number or incorporation date shown on this profile. The company operating www.rs-tec.jp manufactures semiconductor materials, principally reclaiming (“regenerating”) silicon test wafers used in semiconductor fabrication, alongside a smaller prime, or newly manufactured, silicon wafer business, semiconductor-related equipment and materials, and other operations that include solar power generation. Its main reclaimed-wafer production site is the Sanbongi plant in Osaki City, Miyagi Prefecture, Japan, supplemented by reclaim capacity in Taiwan operated through a subsidiary. Industry commentary describes the company as one of the larger global providers of wafer-reclaim services, though specific market-share figures have not been independently verified for this profile. The company is listed on the Prime Market of the Tokyo Stock Exchange under ticker code 3445 (ISIN JP3100350002); its shares first listed on the TSE Mothers market in March 2015 and moved to the TSE First Section in September 2016, ahead of the 2022 market-segment reorganisation of the exchange. According to its own official corporate profile, capital stood at approximately JPY 5,860 million as of 31 December 2025. Consolidated revenue and employee-count figures for a specific reporting period were not independently verified for this profile and are not presented here.
- Company fundamentals
- Corporate linkage & group structures
- Digitized company financials
- Firmographics — websites, social profiles, revenue and employee estimates
Shareholders
5
Shareholders of RS Technologies Co., Ltd.
On-file data lists five institutional shareholders as of 2 August 2026, drawn from a source dataset that references ten total disclosed holder records; only the first five are captured in the available data. The disclosed holdings are: Goldman Sachs International Small Cap Insights Fund, approximately 20.83% (164,000 ordinary shares); Vanguard Tax-Managed Fund — Vanguard Developed Markets Index Fund, approximately 13.66% (107,530 shares); iShares Core MSCI EAFE ETF, approximately 8.34% (65,700 shares); DFA Japanese Small Company Series, approximately 6.71% (52,800 shares); and DFA International Core Equity Portfolio, approximately 4.19% (33,000 shares). All five are institutional fund vehicles, and the interests recorded are direct holdings; no share class is specified in the source data. These five holdings together account for roughly 53.7% of the referenced shares; the remaining shareholder base, and the five additional records implied by the source total, are not captured here. This data was not independently re-verified against Tokyo Stock Exchange large-shareholding filings for this profile. It was also captured under the Japanese corporate registration number carried on this profile (2011001145054), which, as explained in the company description, does not appear to correspond to the company operating this profile’s supplied website; shareholder attribution below should be treated with corresponding caution pending resolution of that entity conflict.
Data availability
Shareholder information for this profile is major shareholders only, and is further limited to five of a referenced ten on-file holder records; it should not be read as a complete shareholder register. Confidence in this data is additionally limited by the unresolved entity-identification conflict described in the company description.
Sources
On-file shareholder dataset, holder records dated 2 August 2026; National Tax Agency Corporate Number Publication Site, houjin-bangou.nta.go.jp, retrieved 17 September 2026.
| Shareholder | Type | Holding | Source Document |
|---|---|---|---|
| Goldman Sachs International Small Cap Insights Fund | 20.8% | National Tax Agency — Corporate Number Publication Site | |
| Vanguard Tax Managed Fund-Vanguard Developed Markets Index Fund | 13.7% | National Tax Agency — Corporate Number Publication Site | |
| iShares Core MSCI EAFE ETF | 8.3% | National Tax Agency — Corporate Number Publication Site | |
| DFA Japanese Small Company Series | 6.7% | National Tax Agency — Corporate Number Publication Site | |
| DFA International Core Equity Portfolio | 4.2% | National Tax Agency — Corporate Number Publication Site |
Officers
9
Directors and officers of RS Technologies Co., Ltd.
On-file data records five active officer entries from a source dataset that references nine total officer records; the remaining four are not captured in the available data. The current roles recorded are General Manager of Business Division (Kunio Hongo), General Manager of Administrative Division (Masayuki Suzuki), Senior Executive Officer (Makoto Kuramoto and Chin-lin Chen), and Senior Executive Officer and Director (Tomatsu Kiyohide). No officer in the available data is recorded as resigned, removed or historical, and no appointment or resignation dates are available for any of the five records. Correspondence-address countries are recorded as Japan for three of the five officers, and as Benin and Switzerland respectively for the remaining two; these are correspondence-address fields only, as captured in the source dataset, and are not evidence of nationality or country of residence for either individual. Nationality is not disclosed for any officer in the sources reviewed for this profile. As with the shareholder data above, this officer dataset was captured under the Japanese corporate registration number carried on this profile (2011001145054), which this profile’s research indicates does not correspond to the company operating this profile’s supplied website; officer attribution should therefore be treated with corresponding caution.
Data availability
Officer information for this profile is partial: five of nine referenced officer records are available, with no appointment or resignation dates and no disclosed nationality for any individual. As above, confidence in this data is limited by the unresolved entity-identification conflict described in the company description.
Sources
On-file officer dataset; National Tax Agency Corporate Number Publication Site, retrieved 17 September 2026.
Registry feed — rows exactly as filed with National Tax Agency — Corporate Number Publication Site, including entries the profile above does not cover.
Group Structure
Group structure of RS Technologies Co., Ltd.
According to official corporate materials published by the company that operates this profile’s supplied website (https://www.rs-tec.jp/), that company has established a subsidiary in Taiwan, RSTEC Semiconductor Taiwan Co., Ltd. (Chinese legal name 艾爾斯半導體股份有限公司), which operates a wafer-reclamation plant in the Tainan Science Park. The Taiwan entity’s own official website describes itself as a subsidiary company established in Taiwan by RS Technologies Co., Ltd., with the plant established in March 2014; the ownership percentage held is not disclosed in the sources reviewed. No verified immediate or ultimate parent company of the website-operating entity was identified; the sources reviewed describe it as an independently listed company. On-file corporate-linkage data recorded no parent, subsidiary or ownership relationship at all for the registration number carried on this profile (2011001145054). The subsidiary relationship described above was identified through the operating company’s own official websites rather than through the on-file linkage data, consistent with the entity-identification conflict explained in the company description, and has not been cross-checked against a Taiwanese corporate registry filing.
Verified corporate relationships
RSTEC Semiconductor Taiwan Co., Ltd. (艾爾斯半導體股份有限公司) — Taiwan — registration number not disclosed — direct subsidiary — ownership percentage not disclosed — active, plant established March 2014 — information dated 17 September 2026.
Data availability
Corporate-linkage information for this profile is partial: a direct Taiwan subsidiary is confirmed through the operating company’s own official websites, but no ownership percentage, Taiwanese registration number or official filing was available to independently verify the relationship. On-file linkage data associated with the registration number carried on this profile reported no group relationships at all, an outcome affected by the entity-identification conflict described elsewhere in this profile.
Sources
RS Technologies Co., Ltd. official corporate profile, rs-tec.jp/corporate/company/, retrieved 17 September 2026; RSTEC Semiconductor Taiwan Co., Ltd. official corporate page, rs-tec.tw/jp/about/, retrieved 17 September 2026.
Get complete shareholder and officer records, ultimate beneficial owner resolution, and ongoing ownership monitoring.
Frequently Asked Questions
What is RS Technologies Co., Ltd.?
RS Technologies Co., Ltd. is the English name used by a Japanese semiconductor-materials company whose principal business is reclaiming ("regenerating") silicon test wafers used in semiconductor fabrication. The company operating www.rs-tec.jp is listed on the Prime Market of the Tokyo Stock Exchange under ticker code 3445.
When was RS Technologies Co., Ltd. incorporated?
This is unresolved on the available evidence. The registration number carried on this profile, 2011001145054, was assigned on 14 January 2022 and, per registry verification, belongs to a different company than the one operating the website supplied for this profile. The company operating www.rs-tec.jp states, on its own official corporate profile, an establishment date of 10 December 2010, under a separate Japanese corporate number, 3010701024500. The 2022 date on file should not be treated as the founding date of the semiconductor company without further verification.
Does the registration number 2011001145054 belong to the semiconductor company at rs-tec.jp?
The available evidence indicates that it does not. Verification of corporate number 2011001145054 resolves to a company written in katakana as 株式会社ＲＳテクノロジーズ, registered in Minato Ward, Tokyo — a different registered address from the company operating www.rs-tec.jp, whose own official materials cite corporate number 3010701024500 and a Shinagawa Ward, Tokyo headquarters. Both entities render as "RS Technologies Co., Ltd." in English, which appears to be the source of the conflict.
What is the stock ticker and listing market for RS Technologies Co., Ltd.?
The website-operating company is listed on the Prime Market of the Tokyo Stock Exchange under ticker code 3445, with ISIN JP3100350002. Its shares were first listed on the TSE Mothers market in March 2015 and moved to the TSE First Section in September 2016, before the 2022 market-segment reorganisation of the exchange.
Where is RS Technologies Co., Ltd. headquartered?
According to its own official corporate profile, the company operating www.rs-tec.jp is headquartered at 1-47-1 Oi, Shinagawa Ward, Tokyo. This differs from the Minato Ward, Tokyo address associated with the registration number carried on this profile, which appears to belong to a different company.
What are the main business segments of RS Technologies Co., Ltd.?
Public materials describe four segments: a wafer-reclamation business that regenerates silicon test wafers; a smaller prime, or newly manufactured, silicon wafer business; semiconductor-related equipment and materials; and other operations that include solar power generation.
Where does RS Technologies Co., Ltd. manufacture its products?
Its main reclaimed-wafer plant is the Sanbongi plant in Osaki City, Miyagi Prefecture, Japan. Additional reclaim capacity operates in Taiwan through a subsidiary, RSTEC Semiconductor Taiwan Co., Ltd., at a plant in the Tainan Science Park established in March 2014.
Does RS Technologies Co., Ltd. have subsidiaries?
Yes. According to official corporate websites, the company operating www.rs-tec.jp has a subsidiary in Taiwan, RSTEC Semiconductor Taiwan Co., Ltd. (艾爾斯半導體股份有限公司). The ownership percentage held is not disclosed in the sources reviewed, and no other verified subsidiary was identified.
Who are the largest disclosed shareholders of RS Technologies Co., Ltd.?
On-file data dated 2 August 2026 lists five institutional holders, the largest being Goldman Sachs International Small Cap Insights Fund at approximately 20.83%, followed by Vanguard Tax-Managed Fund – Vanguard Developed Markets Index Fund at approximately 13.66%. This reflects five of a referenced ten disclosed holder records, not a complete shareholder register, and its attribution is subject to the entity-identification conflict described above.
Who are the directors and officers of RS Technologies Co., Ltd.?
On-file data records five active officers from a referenced total of nine: Kunio Hongo (General Manager of Business Division), Masayuki Suzuki (General Manager of Administrative Division), Makoto Kuramoto and Chin-lin Chen (both Senior Executive Officer), and Tomatsu Kiyohide (Senior Executive Officer and Director). No appointment dates or nationalities are disclosed in the available data.
What is the registered capital of RS Technologies Co., Ltd.?
According to its own official corporate profile, the company operating www.rs-tec.jp reported capital of approximately JPY 5,860 million as of 31 December 2025.
Is RS Technologies Co., Ltd. currently active?
The registration number carried on this profile, 2011001145054, shows an Active status on the National Tax Agency Corporate Number Publication Site. Because that registration number appears to belong to a different company than the one operating www.rs-tec.jp, this status should not be assumed to describe the trading status of the listed semiconductor company.
What is the approximate global position of RS Technologies Co., Ltd. in wafer reclaim services?
Industry commentary describes the company operating www.rs-tec.jp as one of the larger global providers of silicon wafer-reclaim services. This profile has not independently verified specific market-share figures reported by third parties.
Has RS Technologies Co., Ltd. changed its stock exchange listing segment?
Yes. Its shares listed on the Tokyo Stock Exchange Mothers market in March 2015, moved to the TSE First Section in September 2016, and now trade on the Prime Market following the 2022 market-segment reorganisation of the Tokyo Stock Exchange.
What should a compliance or KYB reviewer take from the registration-number conflict on this profile?
A reviewer should treat the on-file registration number, 2011001145054, and its 14 January 2022 assignment date, as unverified for the semiconductor company operating www.rs-tec.jp, and should independently confirm, via the Japan Corporate Number Publication Site or an equivalent registry search, which of the two similarly named entities is relevant before relying on the registry fields shown on this profile.