Every year, more capital chases vertical market software than any other pocket of the software world. Niche, sticky, unglamorous businesses running the back office of an industry nobody else wants to serve. Buyers love them for exactly that reason. They are also, in my experience, one of the most consistently mispriced categories in M&A, because most people evaluating them use the wrong playbook.

I spent nearly five years underwriting these businesses, including time inside the Constellation Software ecosystem, where vertical market software is not a side interest, it is the entire operating philosophy. That vantage point taught me something most generalist buyers never learn: a vertical market software company and a horizontal SaaS company can have identical income statements and still be completely different businesses.

Here is where the playbook usually breaks.

1. Growth rate gets punished when it should get investigated

A horizontal SaaS analyst sees 8 percent annual growth and moves on. In vertical market software, 8 percent might be excellent, because the total addressable market is the number of dentists, or crane operators, or regional credit unions that exist in the country. It is finite and it is knowable.

The question is never "why isn't this growing faster." It is "what percentage of the addressable market does this company already own, and what happens to pricing power once that number gets high." Low growth against a small, well-penetrated market is not a weakness. It is often the entire thesis.

2. Customer concentration analysis misses the real risk

Generalist diligence flags customer concentration as a red flag on a logo-by-logo basis. In a true vertical market, the more relevant concentration risk is the health of the vertical itself. If the target serves regional propane distributors and that industry consolidates from 400 players to 60 over the next decade, the customer count risk shows up as a solvable acquisition problem for someone else, not a product problem for the target.

I have seen deals get a discount for "concentration risk" that was actually a two-year head start on a rollup thesis, simply because nobody bothered to underwrite the customer's industry, only the customer's logo.

3. Switching cost gets modeled like a SaaS metric instead of an operational one

Net revenue retention is the default lens for pricing durability. It works reasonably well for horizontal software, where switching mostly means a new login and a change management project. In vertical market software, switching often means retraining a workforce that is not tech-native, re-certifying against an industry-specific compliance requirement, or ripping out a system that is physically wired into daily operations.

That is a different kind of moat, and it does not show up cleanly in a churn number. The businesses with the widest moats in this category are frequently the ones with the most mediocre-looking retention metrics on a slide, because the metric was built for a different kind of company.

4. "Small market" gets treated as a ceiling instead of a feature

This is the one that costs buyers the most. A market too small to interest a large strategic or a growth-stage VC is also a market too small to attract serious competition. That is not a limitation. In a lot of these businesses, it is the single greatest source of durable pricing power in the entire portfolio. The absence of a well-funded competitor is not an accident, it is the product of the market being deliberately unattractive to everyone except the operator who already understands it.

What this actually means for diligence

None of this is an argument for lowering the bar. It is an argument for using the right bar. Vertical market software rewards a diligence process built around industry structure, not one borrowed wholesale from horizontal SaaS underwriting. The questions worth asking are less about growth curves and more about market boundaries, regulatory dependency, and how deeply the software is embedded in a workflow that is expensive to change.

The buyers who consistently win in this category are not the ones with the biggest models. They are the ones willing to spend real time understanding an unglamorous industry before they ever open a spreadsheet.