The Real Competitor to Every Core System Vendor Is Excel

Robert Lewis is eighth-generation insurance. It started with dynamite. His great-great-great-grandfather imported explosives into South Africa for the mining industry, and couldn’t get anyone to insure the trade — so he and other dynamite transporters banded together and built their own insurance company. That company eventually became a Lloyd’s syndicate.

The direct line from there to INTX runs through Mozambique. Twenty-five years ago, Robert and his brother bought an insurance company there and immediately hit a wall: there was no decent policy administration software available for a carrier their size in that market. So they hired a young developer and built their own. What started as an internal tool became a separate software company, and for most of the following two decades Robert was an investor and board member rather than an operator — until he brought the platform from South Africa and the UK into the United States and went full-time running it as INTX.

Getting INTX ready for the US market meant rewriting the entire codebase — over a million lines — onto a modern Microsoft stack: SQL, C#, and Blazor front to back. That choice was deliberate. Legacy core system vendors write in proprietary languages, which means finding developers who can maintain them is hard, and much of that talent pool sits offshore. Robert wanted a stack any US-trained developer could pick up quickly, insulated from the risk of losing access to offshore engineering talent for political or immigration reasons.

In Episode 142 of InsurTechTalk, Robert and I covered what INTX actually builds, why more than half of insurance professionals still run their real core system in Excel, and why he thinks the industry’s implementation problem is a people problem more than a technology one.

About Robert Lewis

Robert Lewis is the CEO of INTX, a policy administration, core systems, and reinsurance software provider originally built for a carrier he and his brother owned in Mozambique and now rebuilt from the ground up for the US market. INTX is headquartered in Austin and has signed eight clients to date, two of them on the reinsurance side. Before running INTX full-time, Robert spent most of his career as an insurance carrier owner and investor, following an eighth-generation family lineage in the industry that traces back to a dynamite-transport insurance syndicate in South Africa.

What INTX Actually Builds

INTX splits into two related product lines: core systems for carriers and MGAs, and dedicated reinsurance software for both sides of a reinsurance transaction.

On the ceded side, INTX manages a carrier’s treaty and facultative reinsurance contracts end to end — from initial placement, automatically allocating reinsurance the moment a policy is written, and calculating ceding commissions, sliding scales, and both proportional and non-proportional structures
When a claim comes in, the system automatically calculates which portion falls to the treaty, which falls to facultative cover, and how that affects profit commissions, layers, and any required reinstatements
On the assumed side, INTX provides a core system for reinsurers themselves — managing treaties, facultative placements, commissions, loss corridors, and retrocession (the reinsurance that reinsurers buy for themselves)
Robert argues INTX is close to alone in serving both sides of that reinsurance relationship inside one platform, rather than treating reinsurance as an add-on module

Excel Is Still the Industry’s Real Core System

The most striking data point Robert shared came out of a study INTX ran with RSM, surveying 250 insurance professionals spanning MGAs up to tier-one carriers.

55% of respondents said they still run Excel spreadsheets as their actual core system
Robert’s read: it isn’t ignorance — spreadsheets are powerful, flexible, and familiar, born out of frustration with clunky legacy systems that make data extraction painful
The problem is what spreadsheets can’t do: they aren’t auditable, formulas can be silently altered, and there’s no reliable way to run an AI model against data that isn’t structured and consistent across the policy lifecycle
His broader point: no amount of new software matters if underwriting, claims, billing, and reinsurance stay siloed from each other — data has to be one seamless system, not separate systems reconciled later through a data lake

Why Legacy Implementations Take Years

Robert’s sharpest criticism is aimed at the economics and staffing of how core system implementations typically get sold and delivered.

A typical carrier implementation with an established legacy vendor can run into the tens of millions of dollars and take years, often without a clear end date
Much of that cost comes from third-party integrators who don’t actually understand insurance terminology or workflows, slowing every stage of the build
INTX uses its own internal implementation team instead of outside integrators, specifically because they understand both the software and the insurance side of the client’s business
INTX is currently absorbing implementation costs entirely — a deliberately aggressive stance aimed at capital-conscious MGAs and carriers who have been burned before and don’t want another multi-year, budget-devouring migration
Robert’s advice to any carrier undertaking this kind of switch: the projects that go well almost always have one internal champion who understands the full picture — underwriting, claims, reinsurance, and billing — end to end. That person is rare, but their presence is often the difference between a successful migration and a stalled one

Competing With the Aging Guard — and the New Challengers

INTX sits in a market with two very different sets of competitors: entrenched legacy vendors and a newer wave of venture-backed challengers, several of whom, Robert noted, also happen to be building out of Austin.

Against legacy players, INTX’s pitch is architecture and economics — a modern, configurable stack against proprietary code and multi-year implementation cycles
Against newer challengers, INTX’s differentiation is reinsurance depth: treaty and facultative management, retrocession, and loss-corridor complexity that most core-system-first competitors don’t build for
The company has eight clients so far — a small number by design, reflecting how much trust-building each individual carrier relationship requires before they’re willing to move their book onto a new system

Key Takeaways

Excel isn’t a legacy holdout — for a majority of insurance professionals surveyed, it’s still the actual core system, which is a sharper indictment of existing platforms than any vendor pitch
Reinsurance accounting complexity (treaty allocation, sliding scales, loss corridors, retrocession) is a real product wedge that most core-system vendors leave underserved
The biggest cost in a core system migration is usually the integrator, not the software — insurance-literate internal implementation teams are a genuine differentiator, not just a marketing line
Successful implementations depend on having one internal champion who understands the business end to end; that person’s absence is a leading indicator of a project that will stall
Choosing a mainstream technology stack over proprietary legacy code is as much a talent-supply-chain decision as an engineering one