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Founder / Operator·Insurance Brokerage

Greg Zimmer

Chief Executive Officer at Alliant Insurance Services

Irvine, California, USA

GZ
Why they matter

As CEO of a top-8 global insurance broker with a 100+ deal M&A track record, Zimmer sets Alliant's acquisition appetite, specialization strategy, and consolidation pace in the brokerage/MGA space.

Background

Greg Zimmer is Chief Executive Officer of Alliant Insurance Services, one of the largest privately-held U.S. insurance brokerages, based in Irvine, California. He joined Alliant in 1998 as Chief Financial Officer, was promoted to President in 2007, and became CEO in April 2024, succeeding longtime leader Tom Corbett. Before Alliant, Zimmer co-founded a financial services firm sold to GMAC and worked in corporate finance and venture capital at Security Pacific (later Bank of America); he holds a BA in economics/systems science and an MBA from UCLA Anderson.

Notable deals

  • 2024
    Named CEO of Alliant Insurance Services, succeeding Tom Corbett, after 26 years at the firm and 17 as President overseeing 100+ acquisitions
  • 2024
    Led Alliant's acquisition of POPIC, a national captive program manager for multifamily/single-family property owners
  • 2024
    Led Alliant's acquisition of Health Market Solutions (HMS), expanding its direct-to-consumer ACA health insurance business
  • 2024
    Set and publicly articulated a target of ~$5B in annual sales and 20%+ organic growth as new CEO, aiming to move Alliant from #8 to #5 among global brokers

Call-prep brief

Background

  • CEO of Alliant Insurance Services since April 2024; 26-year Alliant veteran (CFO 1998, President 2007, CEO 2024)
  • Career started in corporate finance/VC at Security Pacific, then co-founded a financial services firm sold to GMAC
  • UCLA undergrad + UCLA Anderson MBA

Current Focus

  • Pushing Alliant past ~$5B in annual sales, targeting 20%+ organic growth vs. mid-single-digit industry norms
  • Doubling down on vertical specialization (law firms, construction, restaurants, valet, Native American tribes) over generalist brokerage
  • Expanding consumer-facing lines: Medicare (65+), ACA individual health, and Hispanic-market auto/health products
  • Continuing an aggressive bolt-on M&A pace (POPIC, HMS in 2024 alone) while integrating a workforce approaching 11,000

What He Cares About

  • Talent retention via equity ownership and a deliberately "flat," low-bureaucracy structure
  • "Better, not just bigger" framing for acquisitions — selectivity over pure roll-up volume
  • Employee-impact framing of growth (cites headcount growth from hundreds to 11,000 as his proudest achievement)

Potential Sensitivities

  • Alliant is majority owned by management/producers with Stone Point Capital and PSP Investments as largest institutional shareholders — any conversation implying a sale process should be handled carefully given this ownership structure
  • He's early in the CEO seat (18 months in) succeeding a 30-year incumbent (Corbett, now Executive Chairman) — questions that could read as second-guessing continuity may land poorly
  • Public growth targets ($5B, 20%+ organic) create pressure; probing on whether those are being hit could be sensitive if performance has slipped

Questions to Ask

  1. How is Alliant thinking about platform vs. bolt-on M&A targets in insurance brokerage/MGA right now, and what deal sizes are you underwriting to?
  2. With Stone Point and PSP as institutional holders, how do you think about the timeline and structure for any future liquidity event?
  3. Which specialty verticals (beyond the named ones — law, construction, restaurants, tribal) are you actively building out via acquisition vs. organic hire?

Outreach draft

Subject
Alliant's M&A playbook in brokerage/MGA
Hi Greg, Congratulations on the CEO transition and on the momentum behind Alliant's push toward $5B in sales. Your track record of 100+ acquisitions as President stands out even in a very acquisitive sector, and I'd value your perspective on where brokerage and MGA consolidation goes from here. We're spending time with operators and investors across insurance distribution and would welcome 20 minutes to hear how you're thinking about specialization, platform vs. bolt-on M&A, and where you see the next wave of opportunity. Happy to work around your schedule. Best, [Placeholder Name]

Linked companies

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