The paperwork had done its job, apparently. A friend of Olly Thornton-Berry had been through identity and anti-money-laundering checks four times while trying to buy a London flat. Then came the deposit. He and his partner were each sending half to their solicitor. Her money arrived. His £25,000 went to a fraudster. The checks had been completed; the purchase still fell apart.
Thornton-Berry tells this story with an eye for its cruel detail: the buyer had already been made to feel under suspicion. After all those requests to prove himself, he was the person who lost out. A process could be laborious, reassuringly official and still leave someone exposed. That combination gave Thornton-Berry and his schoolfriend Jack Bidgood a reason to start asking awkward questions.
Bidgood had another complaint, less dramatic but familiar to anyone who has bought a home. Getting through his own lawyer’s onboarding had taken three weeks. The lawyer disliked the process too. Here were customers and professionals, united by their irritation, carrying on with the same procedures. A promising market, perhaps, though a dispiriting way to discover one.
The comfortable job was its own risk
Before Thirdfort, Thornton-Berry invested in software companies in private equity. He knew businesses from the side of the table where someone examines the numbers and decides whether to back them. In 2017, he crossed to the side where the numbers are your responsibility. He left his City job and began Thirdfort with Bidgood.
His parents were unconvinced. Years later, he recalled that they thought he was insane to leave. He came to regard staying as the greater personal risk. This was a choice about what he wanted to spend his time doing, with no guarantee that the new occupation would reward the decision. The comfort of the old job had become part of the argument for leaving it.
There was an earlier rehearsal at Durham University. Between 2009 and 2012, he founded a student loyalty startup that counted 20 local businesses as customers. He later became a CFA charterholder in 2016. The student venture and the investment qualification make a useful pair: an appetite for starting something, followed by a formal education in scrutinising investments.
Ten weeks on the other side of the desk
The founders were outsiders to the profession they wanted to serve. In 2018, they joined Mishcon de Reya’s MDR LAB, spending ten weeks inside a law firm. Their early ambition included secure payments and digital onboarding. Working with the real estate department and risk and compliance teams helped them work out which part of that ambition to build first.
In a joint account of the programme, they recalled arriving with plenty of assumptions about lawyers and technology. During the second week, a long whiteboard session with lawyers produced a moment of recognition: there was a substantial need for what they were attempting. The pleasure of that discovery lay in having the prospective users in the room, able to answer back.
Their surprise was how willingly those lawyers engaged. They described being embedded in the firm and finding enthusiasm for changing the way work was done. Anyone expecting a convenient tale of young technologists dragging a reluctant profession forward would have to amend the script. The lawyers were helping with the invention.
Thornton-Berry later credited the programme with shaping Thirdfort’s product development at a crucial stage. There is a practical reason to dwell on those weeks. A fraud provided the urgency; proximity to the work supplied the detail. A founder could understand why a transaction had gone wrong and still need considerable help designing something a law firm would use.
The customers who spoiled an assumption
Once the app was in use, another confident opinion needed examining. Thornton-Berry kept hearing that older clients would refuse to download an app or would struggle to use one. In February 2020, he published Thirdfort’s figures. Among people who downloaded it, users in their sixties completed verification slightly more successfully than those in their thirties.
The reported pass rates were 96.1% for people in their sixties and 95.8% for those in their thirties. People aged 80 and over reached 97.1%. These were figures about app users, with a clear limitation: they did not include everyone who had been invited to download it. The useful finding was narrower than a declaration about entire generations, and more interesting for being precise.
Who finished the check?
The design allowed someone to use a spouse’s, friend’s or relative’s smartphone while receiving a verification code on their own basic mobile. That offered an answer to a specific obstacle without demanding that every customer acquire a new device. It also complicated the stereotype. The person completing the check and the person owning the smartphone did not have to be the same person.
Thornton-Berry’s argument was grounded in a modest habit: count before concluding. He had suspected the objection was wrong, but he looked for evidence. For someone selling technology to cautious professionals, a small table of completion rates could do work that a speech about the future could not.
Thirty clients become seven hundred
Thirdfort’s subsequent growth made the business substantially harder to run. In March 2022, the founders announced £15 million in Series A investment from Breega and Element Ventures. Their comparison was stark: ten employees, 30 business clients and one industry partner in January 2020 had become 100 employees, 700 business clients and 15 integrated partners.
The app had also been downloaded by more than 500,000 individuals in the UK over the preceding two and a half years. The founders described the experience as “a fire hose to the face”. It is an unusually physical description for a business concerned with documents. Growth arrived as something to withstand as well as welcome.
January 2020 → March 2022. Figures reported by Thirdfort’s founders.
The funding announcement described a broader ambition: bring identity, anti-money-laundering checks, source-of-funds verification and secure payments into a connected experience. For clients, that meant a phone journey that could collect verification information and connect bank feeds. For the professionals, the attraction was less time assembling information scattered across separate requests.
At the end of 2024, Thornton-Berry marked another set of milestones: Thirdfort’s first £1 million month, 1,500 business customers and 2.3 million people who had downloaded and used its app. His accompanying assessment was that the company was still early in its journey. The scale had changed; his appetite for continuing had survived it.
The founder has to change jobs, too
By 2025, his reflections had become more searching about his own contribution. Looking back over eight years, he said he would have done fewer things, put more effort into talent earlier and worried less about market size at the beginning. These are revealing regrets from a former investor. The spreadsheet question had mattered less, in his account, than getting the first stage of execution right.
“Focus is a lesson relearnt repeatedly,” he wrote. The repetition matters. Founders can diagnose a habit accurately and still have to resist it the following week. His admission about hiring was similarly specific: he had accepted advice that delegating it was fine, and later wished he had involved himself more deeply, earlier.
“Focus is a lesson relearnt repeatedly.”
Olly Thornton-Berry, reflecting on eight years of Thirdfort
He has also described a trap beyond £1 million in revenue. Doing everything, cutting corners and giving direct instructions can help a young business survive. Later, those same behaviours can obstruct the people hired to take it further. His point about instructions is particularly uncomfortable: directing capable colleagues can undermine people who know more than the founder.
Read together, these observations suggest a change in the work itself. Starting requires decisions taken with incomplete information. Growing requires other people to make good decisions without waiting for the founder. His advice returns to a practical concern: an approach that once kept a company moving can eventually slow it down.
A million checks, and plenty of judgement
Thornton-Berry has been careful about the limits of the product. Discussing client risk with legal professionals, he observed that firms have different tolerances and need systems that fit their processes. “I don’t think there’s a silver bullet,” he said. It is a useful sentence to hear from someone whose business sells software for a difficult problem.
That position leaves room for professional judgement. A system can gather information, make a pattern visible and help a team decide what to ask next. The practitioner still has to understand the client and the transaction. Thornton-Berry’s interest in configurable systems acknowledges that the same software must serve firms whose working practices differ.
In July 2026, Thirdfort said more than one million buyers, sellers and people providing gifts had used its source-of-funds feature since its 2019 launch. The task still sounds deceptively simple: explain where the money came from, then provide evidence. Behind an ordinary deposit may sit savings, an inheritance, a gift or money moving across borders. Each explanation creates work for someone.
The original £25,000 loss remains a useful way into Thornton-Berry’s story because it puts a person at the end of that work. The friend had complied with the requests and still lost the purchase. Years later, the founder’s questions extend to his own habits: what should he stop doing, whom should he hire, when should he let them decide? He began by questioning an official-looking process. He has found reasons to keep questioning his own.
Keep following the questions
Interviews, writing and a look back at the early days.