Sublime Systems, the Massachusetts-based startup pioneering low-carbon cement, has appointed Chief Operating Officer Rob Davies as its new Chief Executive Officer as the company prepares to scale from pilot to commercial production. The leadership transition marks a new phase for Sublime, which spun out of MIT in 2020 to commercialize a cleaner alternative to traditional cement manufacturing.
Davies brings more than 30 years of industrial and manufacturing experience, including two decades in the cement industry with Blue Circle, Lafarge, and Holcim. He joined Sublime last year as COO after leading operations across the chemicals and advanced materials sectors.
“Leah’s vision to reshape cement production brought together a remarkable team and ecosystem of partners, and is what first drew me to Sublime over a year ago,” Davies said. “I am honored to partner with the Sublime leadership to apply my manufacturing experience and realize the company’s vision through this next phase of commercial growth and industrial expansion.”
Co-founder and outgoing CEO Dr. Leah Ellis, who guided Sublime from its inception to pilot-scale production, will remain actively involved with the company. “I am excited for the next chapter for Sublime Systems, a company I had the great pleasure of leading over the last five years, in part due to Rob and the wonderful team of professionals we have assembled,” Ellis said.
Supporting Davies in the next stage are Bill Brady, appointed Executive Chair, and new board member Dr. Brian Baynes, both seasoned leaders in scaling industrial technologies.
Sublime Systems’ Growth in 2025
Confirming the company’s growth trafectory, Microsoft signed a multi-year deal to purchase up to 622,500 metric tons of Sublime Cement® for its construction projects in May 2025, including environmental attribute certificates to support scalable clean building materials.
Global cement giants Holcim and CRH also committed $75 million to the company, supporting pilot production and future plant expansions. Combined with the new leadership team led by CEO Rob Davies, these moves position Sublime to scale its low-carbon, electrochemical cement technology nationwide.
Read more: Microsoft And Sublime Systems Sign Deal To Scale Clean Cement
