Kareem Amin and Nicolae Rusan did not set out to build a sales tool. In 2017 the pair — who met at McGill University and had worked together at Microsoft — wanted to make programming accessible to people who could not code. Eight years, several pivots, and one much sharper use case later, that idea is worth $7.1 billion.
On September 9 2026, Clay raised $115 million in a Series D led by Wellington Management, with participation from Sequoia, StepStone, Andreessen Horowitz, Perennial, Meritech, DST, CapitalG, BoxGroup, Boldstart, Bloomberg Beta, and Evolution Equity Partners. The valuation of $7.1 billion is more than double Clay’s Series C valuation from just over a year ago and up over 40 percent from a January 2026 employee tender offer. Stay ahead of every US startup funding story at BestStartup US.
What Clay Actually Does — The AI GTM Engine Explained
Clay is not a CRM. It is not a sales engagement tool. It is the layer that sits underneath both — the platform that makes AI agents capable of finding the right customer, understanding why that customer should buy, and taking the first step in the relationship.
Clay gives businesses what it calls “growth agents” — AI systems that identify a company’s ideal customers, monitor intent signals like funding events, hiring activity, and job changes, and then launch personalised campaigns automatically. The company coined the term “GTM Engineers” — go-to-market engineers — for the professionals who run these agents, drawing an explicit parallel with software engineers who run coding agents. Just as a software engineer delegates implementation to an AI coding agent, a GTM engineer delegates prospecting and outreach to a Clay growth agent.
(cite index=”20-1″>Clay unifies a company’s full internal context — CRM data, product usage, campaign engagement, calls, emails — and layers on outside signals like funding events, hiring activity and job changes, building a live understanding of a company’s total addressable market shared across the organisation.
Clay’s Revenue Trajectory and the $1M GTM Engineering Scholarship
(cite index=”20-1″>Clay crossed $100 million in annual recurring revenue in December 2025. The company now serves more than 17,000 customers including Anthropic and Google — the two AI companies that are simultaneously Clay’s most sophisticated users and its most credible endorsers. When the companies building the frontier AI models use your platform to run their own go-to-market operations, it is a product signal that no marketing budget can replicate.
Alongside the Series D announcement, Clay also announced a $1 million scholarship fund to train GTM engineers. The fund will provide training, resources, and community access for the next generation of professionals who want to build careers running AI-powered go-to-market operations. (cite index=”21-1″>The global AI-in-sales market was worth an estimated $50.8 billion in 2026 and is projected to reach $383 billion by 2034. Clay is positioning itself as the platform that trains the professionals who will operate inside that market. Read more US AI startup stories at BestStartup US.
Clay’s Waterfall Feature and Why Data Enrichment Is the Foundation
Clay’s original product insight was about data. When salespeople want to enrich a lead record — adding context about the prospect’s company, role, recent activity, and intent signals — they historically had to manually search each external data source one by one. Clay’s Waterfall feature automates this entirely. It scans external databases sequentially until it finds the required information, then packages the enriched lead data in a format the salesperson or the AI agent can act on immediately.
That data infrastructure — the ability to pull, clean, and unify lead data from dozens of sources automatically — is the foundation on which Clay’s AI agents operate. Without reliable, enriched data the AI agent has nothing to act on. With it, the agent can prioritise leads by revenue potential, draft personalised outreach, generate follow-up emails, create pitch decks, and run ad campaigns — all without human intervention at each step.
Why Wellington Management Led the Round
Wellington Management’s decision to lead the Clay Series D is significant. Wellington is not a traditional venture capital firm. It is one of the world’s largest independent investment management firms with approximately $1.4 trillion in assets under management. When a firm of Wellington’s scale leads a Series D for an enterprise AI startup, it is making a statement about the category rather than just the company. Wellington is betting that AI-powered go-to-market infrastructure is a durable enterprise software category — not a trend — and that Clay has built the leading platform in it.
The participation of CapitalG — Alphabet’s growth-stage investment fund — alongside Wellington is also notable. Google is both a Clay investor through CapitalG and a Clay customer. The overlap between strategic investment and product usage is the strongest signal in the investor roster. Follow every US AI and sales tech funding story at BestStartup US.
Top 10 US AI Sales and GTM Tech Startups to Watch in 2026
- Clay — AI GTM platform — New York — $115M Series D September 2026 — $7.1B valuation — 17,000 plus customers
- Apollo.io — B2B sales intelligence and engagement — Series D — 500,000 plus users
- Outreach — Sales engagement platform — Series G — enterprise sales automation
- Salesloft — Revenue workflow platform — merged with Drift 2024 — AI-powered sales engagement
- Gong — Revenue intelligence platform — $7.25B valuation — AI-powered conversation analytics
- Amplemarket — AI sales copilot — growing fast in mid-market B2B
- Instantly — AI cold email and lead generation — fast-growing sales automation
- Seamless.AI — Real-time B2B contact data — sales intelligence platform
- Lusha — B2B contact intelligence — Series B — go-to-market data platform
- ZoomInfo — B2B data and go-to-market intelligence — listed — the incumbent Clay is competing against
Key Takeaways — Clay $115M Series D September 2026
Clay raised $115 million in a Series D on September 9 2026 led by Wellington Management. Valuation is $7.1 billion — more than double its Series C from one year ago. More than 17,000 customers including Anthropic and Google use the platform. ARR crossed $100 million in December 2025. Clay simultaneously announced a $1 million scholarship fund to train GTM engineers. The global AI-in-sales market is projected to reach $383 billion by 2034. Clay was founded in 2017 by Kareem Amin and Nicolae Rusan. CapitalG and Sequoia participated alongside Wellington in the Series D. The company coined the term GTM Engineer for AI-powered go-to-market professionals. Follow every US startup story at BestStartup US.
Frequently Asked Questions
What is Clay and what did it raise in September 2026?
Clay is a New York-based AI go-to-market platform founded in 2017 by Kareem Amin and Nicolae Rusan. It raised $115 million in a Series D on September 9 2026 led by Wellington Management at a $7.1 billion valuation. The platform serves over 17,000 customers including Anthropic and Google.
What does Clay do?
Clay builds AI growth agents that identify ideal customers, enrich lead data from multiple external sources automatically via its Waterfall feature, monitor intent signals like funding events and hiring activity, and launch personalised outreach campaigns without manual intervention. It unifies CRM data, product usage, and external signals into a live view of a company’s total addressable market.
Why did Wellington Management lead Clay’s Series D?
Wellington Management, with approximately $1.4 trillion in assets under management, led the round as a signal that AI-powered go-to-market infrastructure is a durable enterprise software category. Google also participates as both an investor through CapitalG and a Clay customer — the strongest product validation signal in the round.
What is a GTM Engineer?
GTM Engineer — go-to-market engineer — is a term coined by Clay for the professional role of running AI-powered sales and marketing agents. Just as a software engineer delegates code implementation to an AI coding agent, a GTM engineer delegates prospecting, enrichment, and outreach to a Clay growth agent. Clay announced a $1 million scholarship fund to train GTM engineers alongside the September 2026 raise.
Where can I follow US AI startup news?
Follow every US AI startup funding round, product launch, and company story at BestStartup US — updated every week.
