Agentio, a startup that connects brands with YouTube creators for sponsored content, has raised $40 million in a Series B round led by consumer-focused venture capital firm Forerunner. The funding brings the company’s total raised to $56 million and values it at $340 million. The round includes participation from existing investors Benchmark, Craft Ventures, AlleyCorp, Antler, and Starting Line. The investment comes amid strong growth in creator-led advertising on YouTube. According to Tubefilter, views on sponsored videos rose 28% year-on-year in the first half of 2025, while the number of sponsored videos jumped 54%. Ad spend through creator channels is rising sharply and is projected to surpass traditional media spending in certain categories. Founded in 2023 by CEO Arthur Leopold, former president at Cameo, and CTO Jonathan Meyers, a former Spotify engineer who led automated content marketing, Agentio has grown fivefold since its last funding round in November 2024. The company specializes in using AI to streamline and scale brand-creator partnerships. Early results show strong performance for brands using Agentio. Bombas, a socks and apparel brand, reported a 5.3x higher return on ad spend and a 90% net new customer rate compared to video ads on other platforms. Brands that traditionally took six months to spend their budgets on Meta and Google can now do so in a few months through Agentio with better outcomes. Leopold emphasized that the core challenge before Agentio was scaling creator partnerships efficiently. “Our belief has always been to use AI to automate the ad buying process and deliver better results,” he said. With the rise of AI-generated content, brands are increasingly recognizing the trust creators have with their audiences. Agentio has paid tens of millions of dollars to creators since its launch. Last year, creators on the platform more than doubled their brand partnership earnings within six months. The time to first bid has dropped from 45 to 50 days to under one day, thanks to improved supply and demand matching. On the product side, Agentio has built AI-powered tools to enhance campaign management and content review. Its AI campaign manager helps marketers design campaigns, while a new content review system evaluates draft videos for compliance with briefs and brand safety standards. This eliminates the need for manual video reviews, allowing brands to scale campaigns quickly. The company has also expanded beyond traditional creator categories. For example, a health supplement brand might typically work only with fitness creators, but Agentio’s AI matching identified outdoor creators as a strong fit. While most clients are consumer-focused, demand from B2B organizations is growing. After two years focused on YouTube, Agentio is now beta testing integration with Meta platforms, particularly Reels. It leverages Meta’s partnership ads that appear outside the main feed. Since many creators already have cross-platform presence, especially on Instagram, scaling campaigns has become easier. Looking ahead, Agentio plans to expand to TikTok and Snap in 2026. Eurie Kim, managing partner at Forerunner, said the firm had followed Agentio for over a year, introducing it to key brands that became early adopters. “Unlocking multiple channels was a clear signal that Agentio could become the AI-powered media planning platform of the future,” she said. Agentio has grown from 12 to 35 employees and plans to hire beyond 100 in the coming year.