# Commonwealth Bank of Australia: Proprietary AI

Source: https://www.bankingnewsai.com/banks/commonwealth-bank/proprietary-ai
Last updated: Oct 22, 2026

*Part of the [Commonwealth Bank of Australia AI strategy profile](https://www.bankingnewsai.com/banks/commonwealth-bank).*

## What proprietary AI has Commonwealth Bank built in-house?

Commonwealth Bank builds its own AI applications and agents but does not disclose a foundation model of its own; its large language models come from partners. The oldest in-house system is the Customer Engagement Engine, a machine learning system launched in 2015 that ran over 2,000 real-time models at June 30, 2026. Since 2023 the bank has added CommBank Gen.ai Studio (an H2O.ai-powered environment that produced 50-plus generative AI use cases between June and November 2023), an AI factory on AWS EC2 P5 instances for fine-tuning LLMs (September 2024), and an AI Guardrails-as-a-Service layer. Named systems the bank says its own teams built include CommBank Companion, the in-app assistant 'designed and built by CommBank's own engineering and data science teams' and announced on May 26, 2026; an agentic fraud system built in three months that has helped write three quarters of card fraud rules (April 2026); two cyber threat-hunting agents that cut threat assessment from two days to 30 minutes (March 2026); and Project Coral for tech-debt fixes. Companion is built with Amazon Bedrock, the CommBiz messaging service uses Claude 3 and Cohere models, and staff use ChatGPT Enterprise. Chief AI Officer Ranil Boteju said in September 2026 the bank is looking at 'scaling small language models or using open source to manage costs'. ([Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/02/cba-approach-to-adopting-ai-report-announcement.html), [Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Annual-Report-print.pdf), [iTnews](https://www.itnews.com.au/news/cba-racks-up-50-plus-genai-use-cases-across-the-bank-605089), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/02/amazon-web-services-collaboration.html), [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/05/commbank-companion.html), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/04/ai-agent-spots-fraud-in-real-time.html), [The Register](https://theregister.com/2026/03/17/commonwealth_bank_ai_defense), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/08/ai-powered-engineering.html), [AWS](https://aws.amazon.com/solutions/case-studies/commonwealth-bank-case-study/), [OpenAI](https://openai.com/index/commonwealth-bank-of-australia), [Retail Banker International (via Yahoo Finance)](https://finance.yahoo.com/technology/ai/articles/interview-cba-ai-chief-scaling-091319695.html))

## Which AI systems has Commonwealth Bank built itself, and on what?

Systems the bank describes as built or developed in-house. 'Built on' names the outside model or platform where the bank or its vendor has said so; blank model details mean none were disclosed.

| Platform or model | What it does | Built on | Since | Status | Sources |
| --- | --- | --- | --- | --- | --- |
| Customer Engagement Engine (CEE) | Machine learning system for next best conversations across banking channels; enabled Benefits finder, which has supported more than 400 rebates since 2019 | In-house; generative AI gave a '30x increase in experimentation capability' against the CEE A/B testing framework (February 2024) | 2015 | In production; over 2,000 real-time models at June 30, 2026 | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/02/cba-approach-to-adopting-ai-report-announcement.html), [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf), [Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Annual-Report-print.pdf), [iTnews](https://www.itnews.com.au/news/cba-racks-up-50-plus-genai-use-cases-across-the-bank-605089) |
| Bill Sense | Machine learning that learns a customer's regular payments and predicts when bills will arrive and how much they will be, with the customer confirming each step | Not disclosed | 2020 | In production | [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf) |
| Abuse in Transaction Descriptions model | Detects harassing or threatening payment messages; trained on anonymised high-risk cases from CBA transaction data, retrained on cases the Next Chapter team confirms; flags over 3,600 cases a year | Machine learning, natural language processing and pre-trained LLMs; shared with other banks with H2O.ai | Shared 2023 | In production | [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf) |
| CommBank Gen.ai Studio | Safe environment for experimenting with LLMs; produced 50-plus generative AI use cases between June and November 2023 | H2O.ai | May 2023 | Reported February 2024 | [iTnews](https://www.itnews.com.au/news/cba-racks-up-50-plus-genai-use-cases-across-the-bank-605089) |
| AI factory | Compute for testing and developing AI solutions, 'including fine-tuning and training LLMs' | Amazon EC2 P5 instances (AWS) | September 2024 | In use | [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/02/amazon-web-services-collaboration.html) |
| AI Guardrails-as-a-Service (GaaS) | Shared safety layer for generative AI; in Ceba a groundedness guardrail checks each LLM answer against the retrieved context before it reaches the customer | In-house | Described December 2025 | In production | [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf) |
| Ceba with generative answers | The bank's chatbot, introduced in 2018, handles over 200 tasks and can answer some questions from the public CommBank website by retrieval-augmented generation | LLM provider not named in the report | 2018 (Ceba) | In production | [Yahoo Finance](https://finance.yahoo.com/news/commonwealth-banks-ai-customer-bot-slammed-as-savings-rates-slashed-pathetic-055000109.html), [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf) |
| CommBiz messaging service | Answers business customers from more than 80 CommBiz user guides and FAQs in natural language | Amazon Bedrock Knowledge Bases, Claude 3 and Cohere LLMs, Amazon OpenSearch | Late 2024 | In production | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/02/amazon-web-services-collaboration.html) |
| Compass AI | Generative AI assistant for business bankers; answers knowledge-base questions over three times faster than before | Not disclosed | July 2024 | More than 500,000 questions answered | [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/02/cba-approach-to-adopting-ai-report-announcement.html) |
| CommBank Companion | In-app assistant for budgeting, home buying and business cash flow; multi-agent, with domain teams building sub-agents and purpose-built guardrails for gambling, financial abuse and hardship | Designed and built by the bank's own teams; built with Amazon Bedrock; model not disclosed | May 26, 2026 | Rolling out; one third of customers by August 2026 | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/05/commbank-companion.html), [iTnews](https://www.itnews.com.au/news/cbas-ai-companion-is-expected-to-face-some-hard-questions-628051), [AWS](https://aws.amazon.com/solutions/case-studies/commonwealth-bank-case-study/), [Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Full-Year-Results-Transcript.pdf) |
| Agentic fraud-rule system | Finds emerging fraud and scam patterns, assesses severity and proposes detection rules that analysts approve; contributed to three quarters of card fraud rules | Built in-house in three months on Snowflake's data cloud and the cloud core banking platform | April 24, 2026 | In production | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/04/ai-agent-spots-fraud-in-real-time.html) |
| Cyber threat-hunting agents | One agent tests new threat research against the bank's own data and estate and reports in 30 minutes instead of two days; a second hunts indicators of compromise | Built by cyber staff with the bank's data scientists | Reported March 17, 2026 | In production | [The Register](https://theregister.com/2026/03/17/commonwealth_bank_ai_defense) |
| Project Coral and Lumos | Coral raises pull requests to fix tech debt, designed by graduate and distinguished engineers and runnable on 'any AI development tool'; Lumos is a multi-agent workflow that prepares applications for the cloud | Coral: tool-agnostic; Lumos: built with AWS ProServe, using OpenRewrite and Amazon Q Developer | August 2025; September 2025 | In production | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/08/ai-powered-engineering.html), [iTnews](https://www.itnews.com.au/news/cba-builds-lumos-an-ai-driven-accelerator-to-prepare-applications-for-cloud-620396) |

## Which teams build Commonwealth Bank's AI?

Chief AI Officer Ranil Boteju, who joined from Lloyds early in 2026, says his remit is a single enterprise AI platform for engineers and data scientists, standard controls, guardrails, evaluation and observability, token-cost tracking, and an AI science research lab 'looking at innovations a couple of horizons away'. He told Retail Banker International that over 80% of the bank's 7,800 engineers use 'a combination of bought and built AI-powered coding agents'. ([Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/11/ranil-boteju-chief-ai-officer.html), [Retail Banker International (via Yahoo Finance)](https://finance.yahoo.com/technology/ai/articles/interview-cba-ai-chief-scaling-091319695.html))

The research lab is led by Chief AI Scientist Professor Mary-Anne Williams, who started on June 15, 2026 and heads a team of Distinguished AI Scientists specialising in machine learning, responsible AI, AI security and generative AI. A Human-Centred AI unit set up in November 2024 tests AI experiences with technologists, psychologists, economists, designers and ethnographers. ([Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/05/commonwealth-bank-appoints-first-chief-ai-scientist.html), [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf))

Product systems come from business-line teams. Companion uses a federated model: domain teams across the bank build primary or sub-agents and a central team tests each one before launch, executive general manager Michael Baumann said in August 2026. The fraud agent came from the bank's in-house data science and engineering teams, and the AI Powered Engineering team, formed in July 2024, built Project Coral. ([iTnews](https://www.itnews.com.au/news/cbas-ai-companion-is-expected-to-face-some-hard-questions-628051), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/04/ai-agent-spots-fraud-in-real-time.html), [iTnews](https://www.itnews.com.au/news/cba-plans-to-use-ai-across-entire-software-delivery-614346), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/08/ai-powered-engineering.html))

## When does Commonwealth Bank build AI rather than buy it?

The bank buys models and builds the layer around them. Its 2026 annual report names AWS, Anthropic, Microsoft and OpenAI as strategic partners; the AI factory exists so engineers can fine-tune LLMs on AWS hardware; and AWS's case study says Companion is built with Amazon Bedrock. The contact-centre orchestration platform is built on Microsoft's Copilot Studio, Dynamics 365 and Foundry. ([Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Annual-Report-print.pdf), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/02/amazon-web-services-collaboration.html), [AWS](https://aws.amazon.com/solutions/case-studies/commonwealth-bank-case-study/), [Microsoft Source Asia](https://news.microsoft.com/source/asia/features/how-commonwealth-bank-and-microsoft-are-reimagining-the-future-of-customer-service))

Where it builds, it says it does so for speed or control. General Manager of Cyber Defence Operations Andrew Pade said the bank built its own threat-hunting agents because security vendors 'can't keep up with emerging threats and the bank can't wait for a product'. For Companion the bank stresses that the assistant was designed and built by its own engineering and data science teams inside the CommBank app's secure environment. ([The Register](https://theregister.com/2026/03/17/commonwealth_bank_ai_defense), [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/05/commbank-companion.html))

## What has Commonwealth Bank not disclosed about its own AI?

The bank has not named a proprietary foundation model, said which LLMs it has fine-tuned in the AI factory, or named the model behind Companion or Ceba's generative answers. It has not published how many of the 2,000-plus CEE models are machine learning versus rules, or how many of the 50-plus Gen.ai Studio use cases went into production. ([Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Annual-Report-print.pdf), [Commonwealth Bank of Australia](https://www.commbank.com.au/content/dam/commbank-assets/about-us/docs/our-approach-to-adopting-ai-december-2025.pdf), [iTnews](https://www.itnews.com.au/news/cba-racks-up-50-plus-genai-use-cases-across-the-bank-605089))

Spend on in-house AI is not broken out: the bank reports about A$200 million of measured gross AI benefits for FY26 but no cost for building its own systems. The two published patent applications assigned to the bank, on vector embeddings and on translating non-natural language data, are not tied by the bank to a named system. ([Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Full-Year-Results-Presentation.pdf), [Google Patents (USPTO)](https://patents.google.com/patent/US20250307709A1/en), [Google Patents (IP Australia)](https://patents.google.com/patent/AU2025204862A1/en))

## What does the Commonwealth Bank profile record on this topic?

| Date | Move | Detail | Sources |
| --- | --- | --- | --- |
| Aug 12, 2026 | FY26 results: AI benefits and Companion | The bank reports about A$200 million of measured gross AI benefits for FY26, expects them to double in FY27 and exceed investment, says one third of customers have been given Companion, and discloses a A$1,527 million Anthropic holding in its annual report. | [Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Full-Year-Results-Presentation.pdf), [Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Full-Year-Results-Transcript.pdf), [Commonwealth Bank of Australia](https://commbank.com.au/content/dam/commbank-assets/investors/2026/CBA-2026-Annual-Report-print.pdf) |
| May 26, 2026 | CommBank Companion enters testing | An AI-powered conversational experience in the CommBank app is tested with employees and select business customers, with a consumer test planned in the following weeks. | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/05/commbank-companion.html) |
| Apr 24, 2026 | Agentic fraud system deployed | CommBank deploys an agentic AI system that detects emerging fraud and scam patterns and proposes detection rules, reviewed by analysts before use; built in three months on Snowflake and the bank's cloud core banking platform. | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/04/ai-agent-spots-fraud-in-real-time.html), [Finextra](https://finextra.com/newsarticle/47683/commbank-builds-ai-agent-that-spots-fraud-and-helps-build-defences) |
| Mar 17, 2026 | In-house agentic threat-hunting tools described | At Gartner's Security and Risk Management Summit in Sydney, Andrew Pade said CBA built two agents because vendors could not keep pace: one assesses emerging threats in 30 minutes instead of two days, the other looks for indicators of compromise; weekly threat signals had risen from 80 million to over 400 billion. | [The Register](https://theregister.com/2026/03/17/commonwealth_bank_ai_defense) |
| Feb 4, 2026 | Australian-first AI adoption report | CBA publishes Our Approach to Adopting AI: six responsible AI principles, over 27,600 employees engaged with its AI learning series, scam-detection AI over more than 20 million daily payments, and Compass AI having answered more than 500,000 questions since July 2024. | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2026/02/cba-approach-to-adopting-ai-report-announcement.html), [Finextra](https://finextra.com/newsarticle/47259/commbank-bids-to-ease-customer-fears-over-ai-adoption) |
| Aug 15, 2025 | AI Powered Engineering and Project Coral | CommBank describes an AI Powered Engineering team created in 2024 and Project Coral, an agentic tool that reads monitoring data, analyses code and raises pull requests with fixes for tech debt; engineers must approve every change. | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/08/ai-powered-engineering.html) |
| Jul 1, 2025 | ChatIT IT-support agent in Microsoft's AI Innovators list | Microsoft reports ChatIT, built on Azure and Copilot Studio and launched in 2024, had handled over 2.3 million messages and run more than 12,000 automated IT fixes since its automation function started six months earlier, at about two minutes per fix against 17 minutes for a service-desk call. | [Microsoft Source Asia](https://news.microsoft.com/source/asia/2025/07/01/commonwealth-banks-chatit-helps-employees-fix-it-issues-in-seconds-using-generative-ai) |
| Feb 5, 2025 | AWS collaboration expanded | CommBank and AWS expand their collaboration on cloud and AI; the release says AI adoption had doubled to over 2,000 AI models in 2024, describes a CommBiz GenAI messaging service using Amazon Bedrock Knowledge Bases, Claude 3 and Cohere models, and recalls the AI Factory launched in September 2024. | [Commonwealth Bank of Australia](https://commbank.com.au/articles/newsroom/2025/02/amazon-web-services-collaboration.html) |

## Common questions

### Does Commonwealth Bank build its own AI models?

It builds its own machine learning models and AI applications, but has not disclosed a foundation model of its own. The Customer Engagement Engine has run in-house machine learning since 2015 and held over 2,000 real-time models at June 30, 2026, and the bank trained its own abuse-detection model on its transaction data. For large language models it relies on partners: Claude 3 and Cohere models in CommBiz messaging, Amazon Bedrock for Companion and ChatGPT Enterprise for staff, with an AWS AI factory used to fine-tune LLMs.

### Who built CommBank Companion?

The bank says Companion was 'designed and built by CommBank's own engineering and data science teams', and AWS's case study says it is built with Amazon Bedrock. It is multi-agent: domain teams across the bank build sub-agents and a central team tests each before launch. It was announced on May 26, 2026 and had reached one third of customers by August 2026. The underlying model has not been named.

### What is the Customer Engagement Engine?

A machine learning system CommBank launched in 2015 to choose the next best conversation with each customer across its channels. It enabled Benefits finder, which has supported more than 400 rebates since 2019, and it was used for personalised pricing offers to home-loan customers coming off fixed rates. The 2026 annual report says it runs over 2,000 real-time machine learning models.

### What is CommBank Gen.ai Studio?

An environment powered by H2O.ai that the bank set up in May 2023 for safe experimentation with large language models. CBA's half-year results material in February 2024 said 50-plus generative AI use cases came out of it between June and November 2023 and that over 500 staff had been upskilled on AI tools. CBA led H2O.ai's $100 million Series E in 2021.

### Which AI agents has Commonwealth Bank built in-house?

Named examples: an agentic fraud system built in three months that proposes card fraud rules for analyst approval (April 2026); two cyber threat-hunting agents, one cutting threat assessment from two days to 30 minutes (March 2026); Project Coral, which raises pull requests to fix tech debt (August 2025); Lumos, built with AWS ProServe, for cloud migration; and the sub-agents inside Companion.
## Deeper on Commonwealth Bank

- [What is Commonwealth Bank's AI strategy?](https://www.bankingnewsai.com/banks/commonwealth-bank/ai-strategy)
- [What AI research, patents and partnerships does Commonwealth Bank have?](https://www.bankingnewsai.com/banks/commonwealth-bank/ai-research-patents-partnerships)
- [What technology stack does Commonwealth Bank run?](https://www.bankingnewsai.com/banks/commonwealth-bank/technology-stack)
- [How does Commonwealth Bank govern AI responsibly?](https://www.bankingnewsai.com/banks/commonwealth-bank/responsible-ai)


---

Canonical page: https://www.bankingnewsai.com/banks/commonwealth-bank/proprietary-ai
Part of [BankingNewsAI](https://www.bankingnewsai.com/) — a free daily brief on AI in banking, an AI regulation tracker (43 authorities, 244 documents) and AI-strategy profiles of the 120 largest US banks. Markdown versions of every reference page: append `.md` to the page URL; index at https://www.bankingnewsai.com/llms.txt.