• Skip to main content

  • Home
  • News
    • New Funds
    • New Financings
    • People On the Move
    • Trends and Strategies
  • Transactions
    • New Platforms
    • New Add Ons
    • New Exits
  • Briefly
  • 2025 Salary Survey
  • Member Center
Please enter your username/email.
Please enter your password.
Login
Something went wrong. Please check your entries and try again.
PEP-logo-v9
Flag-small-6-28-24-120x73

January 13, 2026

Private equity's news leader since 2007

Chicago, Illinois

pep-superman-header-80x105-1

"There is a right and a wrong in the universe, and that distinction is not hard to make."

Superman

  • About Us
  • Membership
  • Webinars
  • Store
  • FAQs
  • Advertise With Us
  • Contact Us
Search

manufacturer and distributor of combination locks

Dominus Finds Combination for Lockmasters

September 11, 2020 by John McNulty

Dominus Capital has acquired Lockmasters in partnership with the founding Miller family.

Lockmasters is a manufacturer and distributor of combination locks, tools, hardware, and educational services to government and security professionals, including automotive locksmiths, general locksmiths, and safe and safety deposit box locksmiths. According to the company, it is the leading supplier of combination and safe deposit locks in the United States.

Lockmaster’s educational seminars are branded under the Lockmasters Security Institute and provide training and certification services with courses such as Professional Locksmithing, GSA Authorized Safe & Vault Technician & Inspector Certification, Safe Deposit Box Lock Servicing, and Electronic Safe Lock Servicing.

Lockmasters was founded in 1955 by the Miller family and is headquartered just south of Lexington in Nicholasville, Kentucky (a commercial hub of the lock industry) with an additional facility in Annapolis Junction, Maryland.

The Miller family has been active in the lock industry since 1920 when John C. Miller began working for Diebold Safes. John Miller’s son, Harry Miller, was a lock inventor and safecracker. In 1941, he launched the Lockmasters Security Institute where he taught safecracking and lock-picking to FBI agents and other law enforcement officers. After World War II, he invented the first manipulation-proof lock, which was manufactured by lock-maker Sargent & Greenleaf (S&G). In 1953 he became the president and owner of S&G. Stanley Black & Decker acquired the Nicholasville, Kentucky-headquartered company in 1980 and OpenGate Capital acquired S&G in June 2019.

Lockmasters, led by CEO Mark Miller, is the grandson of Harry Miller. “This next chapter for Lockmasters comes with renewed energy and optimism,” said Mr. Miller. “The industry knows us for our innovative products, technical expertise, hands-on training and customer service. We are excited for the immense growth opportunities our Dominus partnership affords our team and customers. In our 65th year, we are happy to celebrate a new beginning.”

“We are looking forward to partnering with the Miller family and Lockmasters’ team to support the company’s continued growth,” said Bob Haswell, founding partner at Dominus Capital. “The family founders have built a differentiated model with a focus on innovative products, customer service, and technical expertise. We are excited about the opportunities ahead for the company, both organically and through add-on acquisitions.”

New York-based Dominus Capital makes control equity investments in North American-based middle market companies that have at least $10 million of EBITDA. Sectors of interest include business services, consumer products and services, and light industrial. Dominus Capital was founded in 2008.

Private Equity Professional | September 11, 2020

Filed Under: New Platform, Transactions Tagged With: Education, manufacturer and distributor of combination locks

PEP_mainlogo_White

Private Equity Professional
c/o Sun Business Media
PO Box 6610
Evanston, Illinois 60204
Office Direct (847) 920-8010

[email protected]

News

  • Platforms
  • Add Ons
  • Exits
  • Funds
  • Financings
  • People
  • Strategies

Customer Help

  • Why Advertise?
  • PEP Media Kit

Memberships

  • Individual

Advertising

  • Why Advertise?
  • PEP Media Kit

© 2026 Private Equity Professional. All Rights Reserved.