Summation (company)

Summation is an enterprise software company in Bellevue, Washington, that sells what it markets as an "AI analyst": a hosted system that connects to a company's data warehouse, ERP and spreadsheets and produces recurring analyses, reports and forecasts. It was founded in 2024 by Ian Wong, a co-founder and former chief technology officer of the home-buying company Opendoor, and Ramachandran "RC" Ramarathinam, who led Opendoor's core transaction platform. The company emerged from stealth on October 1, 2025 with $35 million from Benchmark and Kleiner Perkins, and opened the product to self-serve signup on September 10, 2026 ^[1][2][3][4].

The legal entity is Summation Technologies, Inc., which does business as Summation ^[3][4]. Much of the company's public messaging is built around a comparison with general-purpose assistants: Summation argues that output from Claude and ChatGPT cannot be relied on for finance and operations work without manual re-checking, and that its own verification layer is what closes that gap. Those are the company's own claims and are treated as such below.

Founders and founding

Summation was founded in January 2024 by Wong and Ramarathinam, who met at Opendoor ^[4]. Wong is chief executive; Ramarathinam is chief technology officer and, according to 425 Business, heads engineering and product architecture ^[4][5].

Wong's record at Opendoor is documented in that company's SEC filings. Opendoor's 2021 proxy statement states that Wong co-founded Opendoor, served as chief technology officer of Opendoor Labs Inc. from April 2014, and served as chief technology officer of the public company from December 2020. It also lists his earlier roles as a software engineer at Prismatic, Inc. and an inference scientist at Square, Inc., and records a B.S. and M.S. in electrical engineering and an M.S. in statistics from Stanford University ^[6]. Opendoor's 2022 proxy adds that "due to a modification to the Company's management structure, Mr. Wong ceased serving as an executive officer of the Company on May 6, 2021" ^[7]. Press accounts and the company's own materials describe him as Square's first data scientist; the SEC filing uses the title "inference scientist" ^[1][5][6].

Ramarathinam most recently led Opendoor's core transaction platform as a director of engineering. Before Opendoor he was a founding engineer at Pro.com and worked at ThoughtWorks and Tata Consultancy ^[4].

In his launch post on X on September 10, 2026, Wong wrote: "I co-founded Opendoor ($10B+ rev). Today, I'm launching Summation. We raised $35M from Benchmark & Kleiner Perkins to build an AI analyst you can trust." ^[8] Opendoor Technologies is a public company, and the revenue figure can be checked against its annual reports. Opendoor's Form 10-K filings report annual revenue of $8.02 billion for 2021, $15.57 billion for 2022, $6.95 billion for 2023, $5.15 billion for 2024 and $4.37 billion for 2025 ^[9]. Annual revenue therefore passed $10 billion in one year, 2022, which was the year after Wong ceased serving as an executive officer.

Funding

Summation disclosed $35 million in total funding when it came out of stealth. GeekWire reported that Benchmark led the seed round and Kleiner Perkins led the Series A, which makes the $35 million a combined figure across two rounds rather than a single raise ^[1]. Neither the company nor the press coverage broke the total into per-round amounts or gave separate closing dates, and the announcement covered both rounds at once. Chetan Puttagunta of Benchmark and Josh Coyne of Kleiner Perkins joined the board ^[1][2]. Coyne is listed as a partner at Kleiner Perkins on the firm's site ^[10].

"Every major technology wave has required a rethink of enterprise infrastructure," Puttagunta said in the launch release ^[2]. Coyne said in the same release: "Executives need not just AI, but AI they can depend on." ^[2]

Product

At launch the company described a "decision-grade AI platform" with three named capabilities ^[2][4]. An AI calculation engine runs enterprise-wide drill-downs with what the company calls continuous, cost-bounded computation, which it says expands the volume of analysis by a factor of 100. Verified Tasks automates workflows such as variance analysis and management reporting and ties results back to source data. Deep Dive orchestrates groups of AI agents that explore "what happened" and "why" questions in parallel and cross-check each other's outputs. Wong, quoted in the release, framed the difference in scale: "Human teams can examine dozens of hypotheses; Summation evaluates thousands in parallel and in real time." ^[2]

The product has been extended several times since. In April 2026 the company announced Reports, which packages an analysis into a formatted deliverable, along with Playbooks, which re-run a defined analysis on a schedule, and Knowledge, a store of company definitions and business logic the system reasons against ^[11]. A deck-generation feature that rebuilds a recurring presentation from a customer's existing template followed in July 2026, and dashboards built on a live data connection later the same month ^[12][13]. Company posts refer to the assistant by the product name Addison ^[12].

The September 2026 release says the platform connects through more than 1,200 integrations and can deliver finished work by email or Slack ^[3]. Published customer material lists connections to Oracle ERP, Microsoft Dynamics 365, Anaplan, Oracle EPBCS and FCCS, Snowflake and Amazon Redshift ^[14]. The company's security page lists Summation under the heading "Compliant With Industry Standards" against SOC 2 Type II and ISO 27001, and says the platform uses AES-256 encryption at rest and TLS 1.2 or later in transit, and operates zero data retention with its foundation model providers ^[15]. The public pricing page, not the security page, is where deployment options are published: the enterprise tier's feature list reads "Cloud, VPC & on-premise deployment options" ^[20].

The verification claim

Summation's central product argument is that a correct-looking output is not the same as a correct one. A September 2026 post by Jojo Chen, a forward deployed product manager at the company, sets out a four-layer model of verification and says Summation's checks cover the first two layers, with tooling for the third and fourth still being built. The post distinguishes verification, the checks the system runs, from auditability, the ability for a user to hover over a figure and see the underlying source. It also argues that consistency has to be checked across a whole report rather than one figure at a time, because numbers can each be individually correct and still contradict one another ^[16].

An August 2026 post by Chris Kim, a forward deployed data scientist at the company, describes an internal test in which the same forecasting task was run twenty times against two unnamed AI models at three levels of complexity, with every cell recomputed rather than read. The post reports that a cheaper model was wrong about half the time once the task resembled real work, and that when a frontier model was asked to verify a full operating financial model twenty times, eighteen runs came back correct, one was clearly broken, and one balanced on every statement while letting cash fall below the floor its own revolver was meant to protect ^[17]. These are self-published vendor results, the models are not named, and no independent replication has been published alongside them. The company's own framing of general-purpose tools is equally pointed: Chen's post calls ChatGPT and Claude "blunt instruments" that "take a swing at anything, and hand you an answer that takes time to manually verify" ^[16].

Customers

The September 2026 release names Fanatics, Lineage and Grid as customers and says the product had been deployed inside companies for about a year before general availability ^[3].

The Fanatics case study, published the day the company left stealth, says Summation was applied to strategic finance workflows at Fanatics Commerce and that the retailer "surfaced over $10 million in upside across growth and cost savings". Andrew Low Ah Kee, chief executive of Fanatics Commerce, is quoted saying "Analyses that once took weeks now happen instantly." ^[14] Low Ah Kee was previously president of Opendoor, where he overlapped with Wong ^[6][7]. The $10 million figure comes from Summation's own case study.

A May 2026 case study covers Lineage, a temperature-controlled logistics operator, and its LinOS warehouse execution system. Summation reports that anomaly detection across ten sites was reduced to roughly five minutes and investigation across the same sites to roughly fifteen minutes. Elliott Wolf, Lineage's vice president and chief data scientist, is quoted: "As LinOS scaled, we needed a faster, more systematic way to monitor performance and investigate issues across sites." ^[18]

An August 2026 case study covers Grid, a Seattle consumer fintech company that had already been using Claude heavily for ad hoc analysis. Grid chief executive Edward Chung is quoted saying: "Claude is amazing for technical users working in their own environments. But we needed to scale the work across the organization. That's where Summation comes in." The study says Grid continues to use Claude and Codex for one-off analysis and uses Summation for work the company runs repeatedly on live data ^[19].

Availability and pricing

Before September 2026 the product was sold through an enterprise motion with a forward deployed team, and the October 2025 release said enterprises were typically live in under four weeks ^[2]. On September 10, 2026 the company opened self-serve signup. The release names two paid plans, Pro at $60 per user per month and Max at $200 per user per month, alongside enterprise plans with dedicated deployment support, custom integrations and additional governance controls ^[3]. The public pricing page lists monthly credit allowances of 12,000 for Pro and 40,000 for Max, plus a free tier with 2,000 credits, and gives enterprise pricing as custom ^[20].

Wong said in the announcement: "Most businesses aren't short on valuable problems to solve. They're short on the analytical capacity to solve them." ^[3]

Location and headcount

The company is headquartered in Bellevue, Washington ^[1][3]. Reported headcount has moved within a narrow band. In October 2025 GeekWire put the team at about 40 people with a majority working in person at the Bellevue office, while 425 Business reported fewer than 40 across engineering, product and go-to-market with about half in Bellevue ^[1][4]. In April 2026 GeekWire reported about 35 employees and said the company was hiring across the same three functions ^[5].

That April 2026 GeekWire piece was prompted by an orange billboard the company put up along State Route 520 in Bellevue, an unusual move for a Seattle-area startup. Wong told the publication: "We're building Summation here in Bellevue, and wanted to do something a little bold and a little playful". He added that "the Seattle/Bellevue area has world-class technical talent, but the scene here has always been understated." ^[5]

Positioning

Summation competes in a segment of enterprise AI that sits between business intelligence tooling and general-purpose chat assistants. GeekWire placed it among a cohort of AI startups that go past reporting and analytics toward shaping strategic decisions directly ^[1]. The company itself claims a new category, "AI-native decision infrastructure", and compares its position to that of ERP in the 1990s and cloud infrastructure in the 2010s ^[2][4].

Its public argument against general-purpose large language models is consistent across the blog, the case studies and Wong's launch post: the models themselves are capable, but a one-off answer from a private session is not something a company can operate on, because it is not shared, not repeatable, and not checked. The counterpart risk, a hallucination or an arithmetic error that survives review because the headline number looks right, is the specific failure the company says its verification layer exists to catch ^[16][17][19].

Independent coverage of Summation has so far come mainly from GeekWire and 425 Business, both regional outlets, and the September 2026 general-availability announcement was distributed as a company press release over PR Newswire rather than reported independently. Revenue, customer counts and per-round funding figures have not been disclosed ^[1][3][4].

References

1. ^1 ^2 ^3 ^4 ^5 ^6 ^7 ^8Taylor Soper, "Opendoor co-founder brings Seattle-area startup Summation out of stealth with $35M in funding", GeekWire, October 1, 2025. geekwire.com/...out-of-stealth-with-35m-in-funding
2. ^1 ^2 ^3 ^4 ^5 ^6 ^7 ^8"Summation Launches Decision-Grade AI Platform to Transform Enterprise Complexity into Profitable Growth", Summation Technologies, Inc. press release distributed by PR Newswire, October 1, 2025. prnewswire.com/...into-profitable-growth-302571721
3. ^1 ^2 ^3 ^4 ^5 ^6 ^7 ^8"Summation Makes AI Analysts Available to Every Business Team", Summation Technologies, Inc. press release distributed by PR Newswire, September 10, 2026. prnewswire.com/...to-every-business-team-302874156
4. ^1 ^2 ^3 ^4 ^5 ^6 ^7 ^8 ^9John Stearns, "Bellevue Startup, Backed by $35M, Introduces AI Platform to Sharpen Enterprise Leaders' Decisions", 425 Business, October 2, 2025. 425business.com/...f44-f1c8-4fb6-af07-459834f149b9
5. ^1 ^2 ^3 ^4Kurt Schlosser, "Seattle-area billboard takes a page from Bay Area playbook: 'Startup energy should be more visible'", GeekWire, April 20, 2026. geekwire.com/...rtup-energy-should-be-more-visible
6. ^1 ^2 ^3Opendoor Technologies Inc., Definitive Proxy Statement (Schedule 14A), filed with the U.S. Securities and Exchange Commission on April 30, 2021. sec.gov/...tm2112233-1_def14a
7. ^1 ^2Opendoor Technologies Inc., Definitive Proxy Statement (Schedule 14A), filed with the U.S. Securities and Exchange Commission on April 8, 2022. sec.gov/...ny20001092x1_def14a
8. ^Ian Wong (@ianwong_), post on X, September 10, 2026. x.com/...2098106891737977191
9. ^Opendoor Technologies Inc. annual revenue as reported on Form 10-K, from the SEC XBRL company concept data for RevenueFromContractWithCustomerExcludingAssessedTax (CIK 0001801169). data.sec.gov/...hCustomerExcludingAssessedTax.json
10. ^"Josh Coyne", Kleiner Perkins. kleinerperkins.com/...josh-coyne
11. ^"Summation Launches Reports: Verified, Exec-Ready Analysis Teams Can Trust, Repeat, and Run On", Summation Technologies, Inc. press release distributed by PR Newswire, April 28, 2026. prnewswire.com/...rust-repeat-and-run-on-302754882
12. ^1 ^2"Your Next Deck Should Update Itself", Summation, July 13, 2026. summation.com/...deckgen-release
13. ^"Dashboards Are Dead. Long Live Dashboards.", Summation, July 30, 2026. summation.com/...dashboards-is-live
14. ^1 ^2"Fanatics + Summation", Summation case study, October 1, 2025. summation.com/...fanatics-summation
15. ^"Enterprise-Grade Protection from Day One", Summation security page. summation.com/security
16. ^1 ^2 ^3Jojo Chen, "How We Think About Verification", Summation, September 2, 2026. summation.com/...how-we-think-about-verification
17. ^1 ^2Chris Kim, "How Summation Beat Leading LLMs on Accuracy", Summation, August 26, 2026. summation.com/...on-beats-leading-llms-on-accuracy
18. ^"Lineage + Summation", Summation case study, May 20, 2026. summation.com/...lineage-summation
19. ^1 ^2"Grid + Summation", Summation case study, August 19, 2026. summation.com/...grid-summation
20. ^1 ^2"Three ways to put Summation to work.", Summation pricing page. summation.com/pricing