Kenneth Greenberg began working in his chosen research field in 2001. Some people suggested he choose another. He stayed. Years later, after co-founding companies and working inside larger organizations, he encountered an idea that would send him back into the business of starting something. The invitation came through a mutual friend who was also a venture investor. Two prospective collaborators had preliminary results and needed someone who could help turn them into a company.
The collaborators were Steve Feinstein and Michael Davidson. Greenberg brought the experience of a researcher who had already crossed into entrepreneurship. Their meeting eventually produced SonoThera, where he serves as co-founder, president, and chief executive officer. His account of the encounter includes three useful words: “I was captivated.” The attraction began with results produced on a small budget. Before the sizeable financing rounds and conference appearances came a much smaller transaction: three people recognizing that their experience might fit together.
That is a good place to begin with Greenberg. His career has involved discovery, but it has also involved the decidedly practical work of assembling organizations. There are inventions to protect, people to recruit, programs to prioritize, and investors to persuade. An idea can arrive looking quite elegant. A company usually arrives carrying a spreadsheet.
A Berkeley invention gets a business address
At the University of California, Berkeley, Greenberg earned a doctorate in visual neuroscience and completed a Kirschstein-NRSA postdoctoral fellowship in MCB neurobiology. The next step included making something that could leave the university. He co-founded Spiral Devices to commercialize technology he had invented during that fellowship. The company was established in 2011 and incubated at the QB3 East Bay Innovation Center. Its first products were sold in 2013.
Those dates tell a compact story. An invention became a company, the company found an incubator, and products reached buyers. The record is particularly useful because it supplies a tangible early chapter in a career that can otherwise disappear into a procession of executive titles. Here was a researcher participating in the conversion of work done at a university into something that could be manufactured, offered, and purchased.
Spiral Devices was previously called Spiral Genomics. Its product was named BioDriver. There is a pleasing directness to that name: it sounds ready to do a job. The episode also establishes that Greenberg's company-building experience predates SonoThera by more than a decade. Starting the later business meant returning to a task he had encountered in a smaller, earlier form.
Commercialization changes the questions surrounding an invention. The laboratory asks whether something works. The business must also ask how it will be supplied, who will use it, and what organization can support it. Greenberg's involvement in Spiral Devices places those questions near the beginning of his professional story. The company had first sales, rather than merely a name. That distinction gives the chronology some welcome substance.
Several jobs hiding inside one career
Greenberg went on to co-found CODA Biotherapeutics and Oncorus. At CODA, his responsibilities included financing, strategic company building, and directing preclinical discovery. At Oncorus, he helped lead financing and scientific strategy. In both organizations, he also contributed as an inventor. These were roles that joined the work of developing an idea to the work of finding the resources to pursue it.
A founder's title can hide an extraordinary variety of tasks. In Greenberg's case, the record spells several of them out. He participated in scientific decisions and in capital formation. That combination helps explain his later role at SonoThera: he had experience with both the proposition being financed and the organization doing the asking. A promising result and a funded company require different forms of attention, even when they begin with the same underlying work.
He subsequently created and led a discovery program at UNITY Biotechnology. Before SonoThera, he led external innovation efforts at Janssen, part of Johnson & Johnson, with responsibilities covering Western North America, Australia, and New Zealand. His work there included supporting strategic partnerships. The geography alone broadens the picture beyond a founder moving between nearby startups.
Research leadership, startup financing, and external innovation offer different views of the same organizational problem: how to connect people, work, and resources. Greenberg has held positions in each. His current title sits at the end of that sequence, rather than floating above it. The preparation was distributed across companies and roles, with each requiring a different relationship to the decisions being made.
Three people, different kinds of experience
The introduction to Feinstein and Davidson brought Greenberg into a collaboration whose starting point was already more substantial than a blank whiteboard. His future co-founders had generated preliminary results. The mutual contact recognized that they needed additional expertise to build an organization around the work. In Greenberg's telling, the introduction answered a specific need.
This origin gives SonoThera a collaborative beginning. Greenberg did not describe dreaming up the whole enterprise alone. He described recognizing the possibilities in work that other people had already done. For a person with his own inventions and earlier companies, that is a useful detail. The founding story leaves room for the work that preceded his arrival and for the contribution he would make afterward.
The division of leadership remains visible today. Feinstein is a co-founder and chief scientific officer. Davidson is a co-founder and executive chairman. Greenberg is the co-founder running the company as president and CEO. The arrangement puts several forms of experience around the same enterprise. It also makes the word “co-founder” do some honest work: there are colleagues in the story, each with a named role.
A good introduction can be a surprisingly consequential business event. It can bring together a person with results, a person with relevant operating experience, and a person who sees why they should meet. Greenberg's account has that structure. The investor's contribution was initially a connection. The company would require much more than that connection, but it gave the prospective partners somewhere to begin.
The first public cheque, then the longer work
In December 2022, SonoThera announced a $60.75 million Series A financing led by ARCH Venture Partners. The investor group included Illumina Ventures, Johnson & Johnson Innovation - JJDC, Vertex Ventures HC, and Medical Excellence Capital. For Greenberg, the announcement marked a company-building milestone as well as a financing event. The work ahead included adding people and developing the organization's capabilities.
Company financing amounts. Bars share a linear scale.
The precision of that number is almost comic. Business conversation often rounds everything to the nearest impressive figure; $60.75 million insists on keeping the quarter. Yet the detail is useful. It identifies a particular financing at a particular moment. It should be read as the company's announced round, with its own investors and purpose, rather than as a measure of Greenberg's personal fortune.
A financing announcement is easy to photograph and difficult to mistake for quiet progress. The work it supports is less obliging. Recruitment, coordination, and decisions about spending do not come with an oversized cheque. Greenberg's earlier experience in financing and research leadership is relevant here because SonoThera needed an organization capable of doing the work after the announcement had finished circulating.
The company also built relationships beyond its investor group. In 2023 it announced a research collaboration with Janssen. Greenberg had previously worked inside that organization; now he was leading a company collaborating with it. The public record puts those two roles on either side of a career transition. It makes partnership a concrete part of his story, alongside invention and fundraising.
What $125 million is actually for
On June 10, 2026, SonoThera announced an oversubscribed $125 million Series B led by Vida Ventures. New and existing investors participated. Rajul Jain of Vida Ventures and Rakhshita Dhar of Leaps by Bayer joined the board in connection with the financing. The round therefore changed both the company's available capital and the group involved in its governance.
Later that month, Greenberg appeared at the BIO International Convention in San Diego on a panel about closing financing rounds above $100 million in a difficult market. It was a subject he could discuss from recent experience. The interesting part of his account was the reasoning behind the amount, and the deliberate choice of investors to approach.
He explained the amount in terms of reaching the company’s next inflection point. That reasoning gives the headline number a destination. A financing round has to support a next stage of work. The practical question is what that stage requires, and how much money gives the company room to reach it.
“It came down to having enough capital to go to the next inflection point.”
Kenneth Greenberg · BIO 2026
His account also described a prioritized investor list. SonoThera started at the top and worked downward. The sequence sounds simple, but it reveals an approach organized around fit and order. Investor selection becomes another form of company design: who should be involved, when should they be approached, and what work must be ready for their scrutiny?
The distinction matters when reading Greenberg's career. He has spent years participating in the construction of companies, and the capital strategy belongs to that construction. The cheque is the visible object. Behind it sit choices about scale, sequencing, ownership, and the next decision the organization needs to make.
Returning to the people
In September 2026, SonoThera appointed Adam Shaywitz to its leadership team. The announcement was another sign of an organization adding experience as its plans developed. A month later, the company was included in Fierce Biotech's 2026 Fierce 15. These events put Greenberg and his colleagues in the news again, following the summer financing.
The recognition supplies an update, but the fuller story is still in the sequence that brought him here. Berkeley, an early commercial venture, additional companies, research leadership, external partnerships, and another founding team: each chapter puts him in contact with a different part of the process. The continuity lies in moving work from one setting into the next.
Greenberg's public career rewards attention to the verbs. He co-founded. He directed. He helped finance. He supported partnerships. He recognized something in other people's results. Those actions give more substance to his profile than an adjective could. They also leave a place for his collaborators, whose expertise and decisions form part of the same record.
The introduction that helped produce SonoThera now sits several years behind a $125 million round and an expanding leadership team. It remains the most revealing opening scene: a researcher and company builder, two prospective partners, and a reason to meet. The meeting became a company. Keeping that company moving has supplied Greenberg with rather more work than an introduction ever promises.