Siena AI

Arbio, headquartered in Berlin, Germany, is building an AI-native property management platform for short-term rentals across Europe. It currently manages over 1,000 apartments and operates real properties in Berlin, Hamburg, Vienna, and Leipzig, with plans to expand to additional European cities. The company has raised a $36 million Series A funding and maintains an engineering team of five engineers. Arbio’s platform uses AI to observe, decide, and act on real-world property operations with humans in the loop, enabling AI-assisted management of short-term rental properties across Europe.

Tacto is building the intelligence layer that connects AI to the physical world of manufacturing, starting with procurement. It operates the leading Procurement Intelligence platform used by more than 300 manufacturers every day, with Enterprise identified as its next major revenue stream. Based in Munich, Germany, the company has 100+ employees and has raised over €50 million from investors including Sequoia and Index Ventures. Tacto maintains strong security and compliance, holding ISO/IEC 27001:2022 Certification marks and DSGVO/EU GDPR conformity, and it is hosted in the EU. The company was founded by CDTM/TUM/Berkeley alumni.

The company aims to make building affordable by leveraging AI to analyze blueprints. It focuses on building computer vision object detection models and coordinating these models, with an emphasis on ML and algorithm development. The company states it prioritizes the intelligence side (ML and algorithms) over the application side. Backed by investors who have funded PlanGrid, Dropbox, and Airbnb, it has strong backing. It is part of Y Combinator's Winter 2025 batch (YCW25).