> ## Content Index > Fetch the complete content index at: https://blog.arbitrum.foundation/llms.txt > Use this file to discover other available public pages before exploring further. # Open House London: Registration Is Now Open - URL: https://blog.arbitrum.foundation/open-house-london-registration-is-now-open/ - Published: 2026-04-14T10:54:05.000Z - Updated: 2026-04-14T11:22:56.000Z - Author: Arbitrum Foundation Registration is now open for Open House London, the next stop in the 2026 cross-continental program. London runs the same format that made New York work - a three-week online Buildathon followed by a three-day in-person Founder House a month later, with technical workshops, product sessions, dedicated mentorship hours and live pitches. Builders will have direct access throughout the program to teams from the Arbitrum Foundation, Offchain Labs and ecosystem partners. With **$415K in prizes and grants up** for grabs, we encourage early-stage founders and builders to apply. Whether you already have a project you’re working on that you want to take to the next level - or whether you’re starting from scratch - Open House London matches your builder energy with dedicated support and resources to enable your next onchain business. If you are building on Arbitrum or thinking about it, this is the place to be [Register Now](https://arbitrum-london.hackquest.io/?utm%5Fsource=arbitrum-blog&utm%5Fmedium=blog&utm%5Fcampaign=oh-london-buildathon) ## **Prize Breakdown** A total of $415K has been earmarked for OH London across its Buildathon and Founder House programs. The Arbitrum Foundation and the Robinhood Chain jointly sponsor the prizes and grants for OH London. ### **OH Buildathon** **Open Category - $70K** The top three buildathon winners will take home $70K. The prize split is as follows: - 1st Place - $40K USDC - 2nd Place - $20K USDC - 3rd Place - $10K USDC A minimum of one of the top three spots will be reserved for a project building on the Robinhood Chain. **AI Agentic Category - $15K** A special category has been reserved for AI agents building on Arbitrum and the Robinhood Chain. The top three winners under this category will share $15K in prizes. At least one out of the top three spots is reserved for projects building on the Robinhood Chain. **Grants - $30K** In addition to the above prizes, $30K USDC has been reserved as grants by the Arbitrum Foundation for winning teams on a case-by-case basis. ### **OH London Founder House** **Open Category - $120K** The top three OH London Founder House winners will take home $120K in total, split as follows: - 1st Place - $60K USDC - 2nd Place - $40K USDC - 3rd Place - $20K USDC Of the top three, at least one will be selected from projects building on the Robinhood Chain. **Robinhood Chain Founder-in-Residence - $60K** This is a special category reserved for projects building exclusively on the Robinhood Chain and fully sponsored by the Robinhood team. **Robinhood Chain Innovation Award - $30K** Teams exhibiting outstanding innovation are eligible for this award. This is reserved for projects building on the Robinhood Chain only and is fully sponsored by the Robinhood team. **AI Agentic Category** **\- $20K** A special category has been reserved for AI agents building on Arbitrum and the Robinhood Chain. The top three winners under this category will share $20K in prizes. At least one out of the top three is reserved for projects building on the Robinhood Chain. **Grants - $70K** In addition to the above prizes, $70K USDC has been reserved as grants by the Arbitrum Foundation to winning teams on a case-by-case basis. Winning teams will receive a portion of the prize money upfront and the remainder tied to development-based milestones, which apply to all tracks except the Agentic categories. ## What OH New York delivered [Open House NYC](https://blog.arbitrum.foundation/nyc-founder-house-concludes-with-340k-in-awards-to-winning-teams/) ran in early March and set the benchmark for the programme. 1712 builders engaged across offline and online activations. 177 projects submitted. $340,000 in prizes and grants awarded. What stood out was the direction of what teams built. Project after project targeted the same gap - the operational services layer that institutional tokenization still lacks. **Tilt Protocol** took $100K in Robinhood Founder in Residence seed funding for an AI-driven management layer on tokenized real-world assets, built natively on Robinhood Chain. **Bond.Credit** won Robinhood's $50K Innovation Award for a credit underwriting engine for autonomous trading agents. **Kustodia** took first place with $60K for programmable escrow across real estate and automotive - fiat to stablecoin, no wallet required. **EqualFi**, which placed third, is already live on the Robinhood Chain testnet with nine index tokens deployed across crypto and stock-based baskets. **Laytus**, in second, introduced a structured prediction market protocol addressing mispriced correlated risk. Winning teams were taken into the Open House Mentorship Programme - eight weeks, equity-free, with up to $100K in additional non-dilutive awards and a Demo Day in front of leading venture firms. **Open House Dubai Postponed** We are postponing Open House Dubai until further notice due to the ongoing regional security situation in the Middle East. We will continue to monitor the situation and hope to be able to reschedule the event towards the end of the year. Registered Dubai participants need to take no further action at this time. We will be in touch if and when we are able to reschedule the event.