Exhibit 21.1

(5/31/26)
Company Name | Place of Incorporation |
API S.p.A. | Italy |
Arnette Polymers, LLC | Massachusetts (USA) |
Carboline Company | Delaware (USA) |
Carboline Global Inc. | Delaware (USA) |
Carboline (India) Private Limited | India |
Clean Bidco Limited (In liquidation) | England & Wales |
Clean Midco Limited (In liquidation) | England & Wales |
Clean Topco Limited (In liquidation) | England & Wales |
DAP Global Holdings, Inc. | Delaware (USA) |
DAP Global Inc. | Delaware (USA) |
DAP Products Inc. | Delaware (USA) |
Day-Glo Color Corp. | Ohio (USA) |
Dryvit Holdings, LLC | Delaware (USA) |
Euclid Admixture Canada Inc. | Canada |
The Euclid Chemical Company | Ohio (USA) |
Eucomex, S.A. de C.V. | Mexico |
Fibergrate Composite Structures Incorporated | Delaware (USA) |
First Continental Services Co. | Vermont (USA) |
Flowcrete Group Limited | England & Wales |
Flowcrete International Ltd | England & Wales |
GJP Holdings Limited | England & Wales |
GSD Distribution LLC | Delaware (USA) |
Kalzip GmbH | Germany |
Key Resin Company | Ohio (USA) |
Kirker Enterprises, Inc. | Delaware (USA) |
Kirker Europe Limited (In liquidation) | Scotland |
Kop-Coat, Inc. | Ohio (USA) |
Kop-Coat New Zealand Limited | New Zealand |
LBG Holdings, Inc. | Delaware (USA) |
Legend Brands, Inc. | Delaware (USA) |
Martin Mathys NV | Belgium |
Modern Recreational Technologies, Inc. | Delaware (USA) |
New Ventures (UK) Limited | England & Wales |
New Ventures II (UK) Limited | England & Wales |
The Pink Stuff Company USA HoldCo LLC | Delaware (USA) |
The Pink Stuff Company USA LLC | Delaware (USA) |
Profile Food Ingredients, LLC | Illinois (USA) |
Radiant Color NV | Belgium |
Ready Seal, LLC | Texas (USA) |
RPM Canada, a General Partnership | Canada |
RPM Canada Finance Company ULC | Canada |
RPM Canada Finance I ULC | Canada |
RPM Canada Holding I ULC | Canada |
RPM CF Holdings, Inc. | Delaware (USA) |
RPM Consumer Group, Inc. | Delaware (USA) |
RPM Enterprises, Inc. | Delaware (USA) |
RPM Europe Finance Designated Activity Company (“dac”) | Ireland |
RPM Europe Holdco B.V. | Netherlands |
RPM Europe Logistics NV | Belgium |
RPM Europe UK Limited | England & Wales |
RPM Funding Corporation | Delaware (USA) |
RPM Global Holdco, LLC | Delaware (USA) |
RPM Holdco Corp. | Delaware (USA) |
RPM Industrial Coatings Group, Inc. | Nevada (USA) |
RPM Industrial Holding, LLC | Delaware (USA) |
RPM International Inc. | Delaware (USA) |
RPM Performance Coatings Group, Inc. | Delaware (USA) |
RPM UK Enterprises Limited | England & Wales |
RPM UK Finance Limited | England & Wales |
RPM UK HOLDCO Limited | England & Wales |
RPM US Finco LLC | Delaware (USA) |
RPM USA Holdco, LLC | Delaware (USA) |
RPM Ventures Netherlands B.V. | Netherlands |
RPOW (France) SAS | France |
RSIF International Designated Activity Company (“dac”) | Ireland |
Rust-Oleum Australia & New Zealand Pty Ltd | Australia |
Rust-Oleum Corporation | Delaware (USA) |
Rust-Oleum Netherlands B.V. | Netherlands |
Schul International Co., LLC | New Hampshire (USA) |
Specialty Products Holding Corp. | Ohio (USA) |
Star Brands (Holdings) Limited | England & Wales |
Star Brands Limited | England & Wales |
Star Brands Manufacturing Ltd | England & Wales |
Star Brands Partnership Ltd | England & Wales |
Star Brands USA Holdings, LLC | Delaware (USA) |
Star Brands USA Inc. | Delaware (USA) |
StonCor Africa Proprietary Limited | South Africa |
StonCor Deutschland GmbH | Germany |
StonCor Group, Inc. | Delaware (USA) |
StonCor Middle East LLC (49% JV) | United Arab Emirates |
TCI, Inc. | Georgia (USA) |
T.M.P. – CONVERT SAS | France |
Tor Coatings Limited | England & Wales |
Toxement S.A.S. | Colombia |
Tremco Asia Pacific Pty Limited | Australia |
Tremco Barrier Solutions, Inc. | Delaware (USA) |
Tremco CPG Germany GmbH | Germany |
Tremco CPG Inc. | Delaware (USA) |
Tremco CPG Manufacturing Corp. | Delaware (USA) |
Tremco CPG Netherlands B.V. | Netherlands |
Tremco CPG Sweden AB | Sweden |
Tremco CPG UK Limited | England & Wales |
Tremco Holdings, Inc. | Delaware (USA) |
tremco illbruck Group GmbH (Being merged) | Germany |
Tremco Incorporated | Ohio (USA) |
United Construction Products, LLC | Colorado (USA) |
Universal Sealants (U.K.) Limited | England & Wales |
Viapol Ltda. | Brazil |
Watco UK Limited | England & Wales |
Weatherproofing Technologies, Inc. | Delaware (USA) |