Global investment firm Blackstone announced on May 20 its investment in a Korean robotics company, citing the humanoid and automation market as being in the early stages of explosive growth. The undisclosed investment values the company at approximately 1 trillion won according to investment banking industry assessments. The investment focus centers on actuators — robot joints that account for over 60% of humanoid robot production costs. SPG, a Korean component manufacturer, has attracted retail investor attention this week as global capital flows toward joint components alongside artificial intelligence development. SPG is the only domestic company capable of producing all three types of industrial robot reducers (planetary, SH, SR), positioning it as a key supplier in the emerging humanoid robotics supply chain.
SPG Transitions from Appliance Motors to Robot Joint Production
SPG was established in 1991 as a component manufacturer producing fan motors for white goods appliances like refrigerators and geared motors for factory automation. The company supplied global appliance manufacturers including GE and Whirlpool, growing quietly with operating profit margins around 3% on commodity fan motor products.
The company's strategic shift focused on reducers — components that convert a motor's fast rotation into slower but more powerful movement. In robotics applications, reducers enable robots to lift heavy loads while maintaining precise fingertip control, with each joint requiring this component. SPG became the only domestic company to localize all three industrial robot reducer types (planetary, SH, SR) in a market long dominated by German and Japanese manufacturers.
The capability to produce all three reducer types allows SPG to adapt to varying robot designs and customer requirements. Industry observers note that in the humanoid market, which lacks standardized form factors, companies offering full product lineups can address diverse customer needs compared to those specialized in specific configurations.
Financial results reflect this business model transformation. Revenue reached 341.7 billion won last year, down approximately 12% year-over-year, while operating profit increased to 17.9 billion won, up over 45%. The improved profitability resulted from a higher proportion of high-margin reducers replacing low-margin motors in the sales mix. Precision reducers accounted for 4% of revenue last year.
SPG Supplies Reducers to Samsung-Backed Rainbow Robotics and Pursues US Market Entry
SPG serves as the sole reducer supplier to Rainbow Robotics, a robot manufacturer with Samsung Electronics shareholding. The supply relationship covers Rainbow Robotics' entire product lineup including collaborative robots, dual-arm robots, and quadruped robots. As Samsung Electronics expands its robotics business, SPG's position as exclusive supplier creates direct exposure to this growth. Rainbow Robotics' expansion into defense applications with quadruped robots provides potential for stable government orders. Securities analysts project Rainbow Robotics-related sales reaching approximately 16 billion won in 2027, roughly double the 2026 level.
SPG has developed an integrated actuator product called SDD, combining reducer, motor, and controller components. The company reports heat generation improvements of over 30% compared to existing products. Following joint development with the Korea Institute of Machinery and Materials, SPG secured domestic orders and participated in North America's largest automation trade show in June. Multiple US companies are under non-disclosure agreement review following the exhibition, though no contracts have been finalized.
IBK Securities projects SPG's 2026 revenue and operating profit to increase 6.2% and 24.2% respectively year-over-year, maintaining a buy rating with a 100,000 won target price. This represents 51.5% upside from the July 16 closing price of 66,000 won.
High Valuation and Global Competition Present Investment Considerations
SPG's stock price has risen 144% over the past year, reaching a 52-week high of 158,100 won before adjusting to close at 66,000 won on July 16. The price-to-earnings ratio based on last year's net profit stands at 197 times.
The robot reducer market has been dominated by two Japanese companies — Harmonic Drive and Nabtesco — which hold approximately 75% of global market share. While SPG's position as the only domestic full-lineup producer represents a competitive advantage, the company remains a challenger in the global market.
Key monitoring factors include the conversion of US company NDAs into actual orders and whether Rainbow Robotics supply volumes grow as projected. Given the high dependency, Samsung's robotics business pace directly influences SPG's financial performance.
FAQ
What types of robot reducers does SPG produce?
SPG is the only domestic Korean company producing all three types of industrial robot reducers: planetary, SH, and SR. This full lineup capability allows the company to serve different robot designs and customer specifications in a market where humanoid form factors have not yet been standardized.
What was SPG's financial performance last year?
SPG reported revenue of 341.7 billion won in the most recent year, down approximately 12% year-over-year. Operating profit increased to 17.9 billion won, up over 45%, as higher-margin precision reducers replaced lower-margin motor products in the sales mix. Precision reducers accounted for 4% of total revenue.
