Together AI Raises $800 Million to Expand Infrastructure for Open Models

Together AI, a company that rents out compute power for open source models, has announced the close of an $800 million Series C funding round. The company's new valuation stands at $8.3 billion, more than double what it was in its previous round less than a year and a half ago.

The round was led by Aramco Ventures, a fund tied to the Saudi oil giant. Also participating were Vista Equity Partners, General Catalyst, Emergence Capital, Nvidia, March Capital, Pegatron, and S Ventures, the venture arm of SentinelOne. The investor list shows just how widely capital is flowing into AI infrastructure, from oil funds to hardware makers.

Together AI's Business Model

Together AI, founded in 2022 by Vipul Ved Prakash, Percy Liang, and Ce Zhang, doesn't build its own foundation models. Instead, it offers GPU clusters and a platform for training and running other companies' models, mostly ones released under open licenses, such as DeepSeek, Nemotron, MiniMax, and Kimi.

The company said its annualized bookings topped $1.15 billion last quarter. Among its paying customers it names Cursor, Cognition, and Decagon, companies building their own AI products on someone else's infrastructure rather than investing in their own data centers.

Why Open Models Are Gaining Ground

Behind Together AI's scale is a clear market trend. According to data cited around the round, industry-wide use of open source models has tripled over the past twelve months. Companies are increasingly choosing cheaper, open alternatives over expensive closed models from OpenAI, Anthropic, or Google, especially where the cost per query matters more than squeezing out the highest possible quality.

Together AI says customers using open models on its platform save anywhere from six to sixty times more than they would with closed models, depending on the use case. The new funding will go mainly toward expanding infrastructure, which the company plans to scale up roughly fiftyfold over the next five years.

What It Means for Polish Companies

For Polish companies and startups building AI-based products, Together AI's round signals that the "rent compute for an open model" approach is becoming an increasingly viable alternative to signing expensive contracts with closed API providers. Lower inference costs translate directly into lower bills for companies charged by the token or the query rather than by an annual license.

Growing competition between infrastructure providers for open models and the giants offering closed systems also means more options when choosing an AI vendor for local deployments, including for companies that want to keep their data closer to home rather than sending it to the US clouds running GPT or Claude.

The scale of the investment, nearly a billion dollars in a single round for a company that doesn't train models itself but simply rents out compute power, also shows where the biggest capital is currently flowing in the AI industry. Investors are betting not just on model builders but increasingly on the infrastructure layer that lets those models run cheaply at scale.

Sources: Neocloud Together AI raises $800M, leaps to $8.3B valuation (techcrunch.com), Together AI Raises $800 Million at $8.3 Billion Valuation (businesswire.com).