Joshua Dinneen

Chief Executive Officer Blue Mantis

Last Reviewed: September 26, 2026

Executive Summary

Joshua (Josh) Dinneen is Chief Executive Officer of Blue Mantis, a Portsmouth, New Hampshire IT services provider focused on managed services, cybersecurity and cloud, and known until 2023 as GreenPages. He came into the company as a founder whose business was acquired: GreenPages bought his advisory firm, Norwell Technology Group, in 2018, and over the next five years he moved through strategic services, sales and marketing, chief revenue officer and president roles before taking over as CEO on 1 January 2024. His tenure so far has included a change of majority owner, a three-company acquisition, and recognition as an MSP Executive of the Year in 2025. He is a U.S. Marine Corps veteran.

Career Highlights

• CEO of Blue Mantis since 1 January 2024, succeeding Ron Dupler, who became Chairman.
• Founded Norwell Technology Group, a boutique IT and security advisory firm, in 2015, and led it as President and CEO until its acquisition by GreenPages in 2018.
• At GreenPages / Blue Mantis: President of Strategic Services (2018), President of Sales and Marketing (2019), Chief Revenue Officer (March 2021) and President (March 2023).
• As CEO, led the company through Recognize’s majority investment in September 2024 and the acquisition of TELigence Partners, Brevin Systems and Calkins Networks announced in March 2025.
• Named an MSP Executive of the Year at Channel Partners’ 2025 MSP Summit.
• Blue Mantis was ranked number 18 on the 2026 MSP 501 list.

Professional Journey

Blue Mantis describes Dinneen as a 25-year veteran of the managed service provider and IT services industry, and Blue Mantis says his earlier career included senior leadership positions at high-growth technology firms, including managing mergers and acquisitions. Those earlier employers are not named in any source read. He is also a veteran of the U.S. Marine Corps.

In 2015 he founded Norwell Technology Group, a boutique IT and security advisory firm, and ran it as President and CEO. In 2018 NTG was acquired by GreenPages, and Dinneen joined as President of Strategic Services. He took on sales and marketing as President of Sales and Marketing in 2019, was promoted to Chief Revenue Officer in March 2021, and became company President in March 2023, the year GreenPages rebranded as Blue Mantis.

The board named him Chief Executive Officer effective 1 January 2024, with Ron Dupler, the long-serving CEO, moving to Chairman. At the time the company was backed by Abry Partners, which had invested in 2020. In September 2024 Recognize, a private equity firm that invests in technology services businesses, announced a majority investment in Blue Mantis, with Abry remaining a minority investor; Dinneen said the team was “completely aligned with Recognize on key strategic imperatives.” In March 2025 the company added TELigence Partners, Brevin Systems and Calkins Networks to expand its carrier services and networking practice into markets including Albany, Buffalo, Burlington and Rochester.

When Channel Partners named him an MSP Executive of the Year in September 2025, Blue Mantis credited his leadership with a compound annual growth rate of nearly 30 percent, customer retention above 97 percent, and a shift from a traditional product reseller to a services-led provider, with five-year growth of more than 400 percent in cybersecurity and managed services by the company’s own figures. The company, which has offices in greater Boston, Tampa Bay, Toronto and Bangalore, placed 18th on the 2026 MSP 501.

Education

No education record was found in any source read.