Lower middle market private equity
We Partner with Founders to Build Lasting Businesses.
invests in founder-led and family-owned businesses with enterprise values of $20M-$200M in the U.S. and beyond.
What We Do
Specialized expertise for demanding clients.
Specialty Manufacturing
Precision and contract manufacturers with differentiated capabilities and defensible market positions.
Industrial Services
Mission-critical service providers with recurring revenue and strong customer relationships.
Value-Added Distribution
Distributors with technical sales capability and inventory-light models.
Business Services
B2B services companies with high retention and scalable operating models.
Why Sentinel
Built for partnership, not financial engineering.
Operational Partnership
We invest behind management teams and provide strategic support without replacing leadership.
Long-Term Orientation
Flexible hold periods aligned with building real value, not exit timelines.
Founder-Friendly Terms
We structure deals that protect seller equity, employee continuity, and brand legacy.
Portfolio
Recent work.
Platform Investment
Precision Components Holdings
Manufacturing
Partnered with founding family
2023$45M-$65M
Platform Investment
National Industrial Services
Industrial Services
Management-led partnership
2022$55M-$80M
Add-On Acquisition
Regional HVAC Services
Industrial Services
Added to portfolio platform
2024Undisclosed
Our Team
Leadership you can trust.
Marcus J. Sentinel
Founder & Managing Partner
25 years in private equity and investment banking with deep industrial sector expertise.
Katherine L. Adler
Partner
15 years investing in lower middle market businesses with operational value creation focus.
This website and all people listed are fictional and provided as a Valdr Systems demonstration build.