With roughly 240 employees across hubs in Seoul, San Jose and Tokyo, Upstage is best known in enterprise AI circles for Solar Pro 4 and its Document Parse OCR engine. Teams already using Naver-ecosystem or Korean-language tools should evaluate Upstage before defaulting to a US-only foundation model provider.
Upstage is a Seoul-based AI company founded in October 2020 by former Naver Clova AI lead Sung Kim. It builds the Solar family of large language models and Document AI parsing tools, competing on price-performance and Korean-language accuracy against larger US and Chinese foundation-model labs.
Founded: 2020 · HQ: Seoul, South Korea · Team: 200-300 · CEO: Sung Kim · Funding: ~$270M total across Series A-C as of the Apr 2026 Series C first close (incl. a $45M Aug 2025 Series B bridge; lead: Sazze Partners) · Valuation: $1B (Series C, Apr 2026) — South Korea's first generative-AI unicorn
About Upstage
Upstage was founded in October 2020 by CEO Sung Kim, a former Hong Kong University of Science and Technology professor who spent 2017 to 2020 as founding head of Naver Clova AI. Co-founders Hwalsuk "Stan" Lee, who led Naver Clova's Visual AI and OCR team and became CTO, and Eunjeong "Lucy" Park, who led Naver's Papago language team, joined him. The company is registered in Gangnam-gu, Seoul, with hubs in San Jose (opened as its US headquarters in 2024) and Tokyo. Its founding thesis was "full-stack AI": pairing a proprietary foundation model with document intelligence so Korean enterprises would not have to stitch together US-built LLMs and separate OCR vendors. Upstage's flagship line is the Solar family. Solar Pro 2, a 31-billion-parameter model with a hybrid reasoning mode, shipped in July 2025 and broke into the global frontier tier with a composite score of 58, ahead of GPT-4.1 (53) and Llama 4 Maverick (51), the first Korean-built model to do so. Solar Pro 3, a 102-billion-parameter mixture-of-experts model activating 12 billion parameters per token, followed on January 26, 2026 with a production-scale reasoning upgrade, then roughly doubled its agentic benchmark scores in a March 2026 update. Solar Open 2, released July 22, 2026, is a separate 250-billion-parameter open-weight mixture-of-experts model activating just 15 billion parameters per inference, with context windows up to 1 million tokens, designed to run on two Nvidia H200 GPUs. Solar Pro 4 launched August 10, 2026 as an agent-first model built for multi-step task completion rather than single-shot answers. Alongside the models, Upstage sells Document Parse and Universal Information Extraction (OCR and layout-analysis APIs for digitizing forms and contracts) and Upstage Studio, a document-AI agent workflow builder. In the six months before this profile was written, Upstage closed the first tranche of a $120 million Series C (April 2026), finalized its acquisition of AXZ, operator of the Daum web portal, from Kakao via a share swap (May 2026), signed an MoU with LG Electronics for an on-device small language model for LG Gram laptops, and entered talks to buy roughly 10,000 AMD chips to expand Korean AI compute. In December 2025 it hired KB Securities and Mirae Asset Securities to prepare a Korea Exchange listing. Upstage has raised approximately $270 million across Series A through C as of the Series C first close: a $72 million Series B (2024) led by SK Networks and Shinhan Venture Investment, a $45 million Series B bridge (August 2025) backed by Korea Development Bank, Amazon and AMD, and the $120 million Series C led by repeat investor Sazze Partners with Premier Partners, Shinhan Venture Investment, Mirae Asset Venture Investment, KB Securities and InterVest returning, plus new investors Axiom Asia, Hyundai Motor Company, Kia Corporation, Woori Venture Partners and Industrial Bank of Korea. The round pushed Upstage's valuation past $1 billion, making it South Korea's first generative-AI unicorn. Kakao separately holds an estimated 15 to 25 percent stake through the AXZ share swap rather than a priced cash round. Upstage earns revenue from per-token Solar API consumption and from enterprise contracts and on-premises licensing for Document Parse and related tools. Management has cited year-over-year revenue growth above 130 percent, tied to Solar and Document Intelligence demand, in connection with the Series C round; no audited public revenue figure has been disclosed. CEO Sung Kim leads the company; CTO Stan Lee oversees model and vision research. Co-founder Lucy Park has held the Chief Scientific Officer, Chief Product Officer and, since the 2024 San Jose opening, US CEO titles. Reported headcount grew from roughly 141 employees in earlier filings to 239 by the end of May 2026, tracking the Series C raise, putting current team size in a 200 to 300 range across Seoul, San Jose and Tokyo. Upstage states its mission as building "intelligence for the future of work" and publishes technical blog posts on Solar's architecture and benchmarks alongside each release. It has not published a formal Responsible Scaling Policy or named third-party red-teaming partners, unlike frontier US and UK labs; its public compliance posture centers instead on SOC 2 (Type I), ISO/IEC 27001, ISO/IEC 27701 and Vanta-verified HIPAA badges shown on its corporate site, without a dedicated public trust center. Upstage competes with smaller and mid-sized labs such as Mistral AI, Cohere and Alibaba's Qwen team on price-performance, and with OpenAI, Anthropic and Google DeepMind specifically on Korean-language and document-intelligence workloads, where its home-market data and the newly acquired Daum portal give it a distribution edge those labs lack in Korea. It trails all three on raw frontier benchmark ceiling and on the size of its third-party integration ecosystem. Upstage is pursuing a Korea Exchange IPO as early as the second half of 2026, with a first-half-2027 deadline, which would make it the first post-ChatGPT generative-AI startup to go public in South Korea; press coverage has cited analyst expectations of a post-IPO valuation between 2 and 3 trillion Korean won. Its near-term roadmap is agent-centric: Sung Kim has said AI agents will "go commercial" in 2026, a framing reflected in both the Solar Open 2 and Solar Pro 4 launches.
Mission
Build intelligence for the future of work.
Products
- Solar Pro 4 (Flagship agentic LLM (API)): https://www.upstage.ai/blog/en/solar-pro-4
- Solar Open 2 (Open-weight MoE LLM (250B/15B active)): https://www.upstage.ai/blog
- Document Parse (OCR & document-layout API): https://console.upstage.ai/docs/models
- Upstage Studio (Document-AI agent workflow builder): https://www.upstage.ai/products/studio
- AI Space (Document-based AI workspace): https://www.upstage.ai/products/ai-space
Upstage Models on HokAI
Compliance
SOC 2 Type I, ISO/IEC 27001, ISO/IEC 27701, HIPAA (Vanta-verified)
Links
Frequently Asked Questions
How much funding has Upstage raised?
Total disclosed funding is roughly $270 million through the April 2026 first close of Upstage's Series C, which followed a $45 million bridge round the prior August. That $120 million Series C, led by Sazze Partners with new backers Hyundai, Kia and Axiom Asia, pushed the company past a $1 billion valuation as South Korea's first generative-AI unicorn. Kakao also holds an estimated 15 to 25 percent equity position, acquired through a 2026 share swap rather than a cash investment.
What products does Upstage make in 2026?
Upstage's 2026 lineup centers on the Solar LLM family: Solar Pro 4, an agent-first flagship that went live August 10, 2026 at $0.30 per million input tokens and $1.20 per million output tokens, and Solar Open 2, a 250-billion-parameter open-weight model that activates 15 billion parameters per inference and runs on two Nvidia H200 GPUs. Outside the model line, Document Parse and Universal Information Extraction handle OCR and layout analysis for enterprise paperwork, and Upstage Studio packages those into document-AI agent workflows.
How does Upstage handle data privacy and compliance?
Upstage's corporate site shows Vanta-verified badges for SOC 2, ISO/IEC 27001, ISO/IEC 27701 and HIPAA, though there is no dedicated public trust center or downloadable report. Document Intelligence workloads can run entirely inside a customer's own AWS account for data residency, and Upstage states it does not use customer API data to train its models by default.
Who are Upstage's main competitors?
On price-performance, Upstage's closest peers are smaller frontier labs like Mistral AI, Cohere and Alibaba's Qwen models; on Korean-language and document-intelligence workloads specifically, it goes head-to-head with OpenAI, Anthropic and Google DeepMind. It wins on cost, Korean-language accuracy, and the consumer distribution its new Daum acquisition provides; it loses on raw frontier benchmark ceiling and the breadth of third-party integrations built around GPT, Claude and Gemini.
How do you start using Upstage's products?
Developers can sign up at console.upstage.ai, generate an API key, and call the Solar chat completions endpoint within minutes using Upstage's published quickstart guide. Enterprises evaluating Document Parse or an on-premises deployment typically start through Upstage's sales team rather than self-serve signup, since pricing there is quote-based.