Fernando Castiñeiras
About Fernando Castiñeiras
Fernando Castiñeiras was born in 1967 in La Coruña, Spain. According to a biography published by IDBank, he studied economics at Universidad Complutense de Madrid and later completed a master's in information systems management at Universidad Politécnica de Madrid and an Executive MBA at Warwick Business School. He started his career at Arthur Andersen in Madrid and worked in the Global Investment Banking Group in London between 1996 and 2002.
In 2002 he co-founded Management Solutions, a multinational consulting firm. Athos Capital's team page says he scaled it to 2,000 employees. He founded Athos Capital in 2016 and is its managing partner. Public records also list him as founder of Sputnik Capital, an alternative investment manager, and as a director at Stage Ventures. In 2024 he joined the council of ID Bank in Armenia.
Athos Capital says he has invested in digital ventures since 2007. A European Angels Fund list names Sputnik, a business angel syndicate, with Castiñeiras as its contact. Kfund's list of active Spanish investors names him as the contact for Athos Capital in its seed funds category.
On LinkedIn he has written that he first invested in Pablo's earlier company, Buguroo, more than 10 years before Athos backed Pablo's later company, Acoru. A 2022 UPPSTART post describes Athos as sector-agnostic, investing across Europe, with more than 15 startups in its portfolio at that time.
The AI round on the Lounge deals desk is Mafer AI's €2M pre-seed (2026-06). Press coverage in May 2026 named him among the business angels in the round. Kfund, 4Founders Capital, Masia and Lavanda Ventures were the institutional investors.
Mafer AI is a Barcelona startup. It builds MaferOS, an AI operating system for R&D teams in formulation industries such as chemicals, cosmetics and fragrances. No other AI-specific investments by him could be confirmed from public sources.
Athos Capital's public profile says it finances seed, early and growth-stage companies, mainly in Europe and with a focus on Spain. It takes minority stakes and says it invests between EUR 100K and EUR 1.5M depending on stage and company type. That range is the firm's, not a personal angel check size, and he has not published a personal check size. His 2022 UPPSTART post describes Athos as looking for seed and Series A startups and as sector-agnostic.
- Mafer AI: AI operating system for formulation R&D teams, backed in its €2M pre-seed round, reported May 2026.
- Wenalyze: data analytics startup that closed a €1.7M round in March 2022, led by Athos Capital.
- Acoru: company founded by Pablo and David, which Athos joined as an investor. He has said he invested earlier in Pablo's previous company, Buguroo.
- Buguroo: earlier company of Acoru's co-founder Pablo, in which he invested personally. The year is not stated.
- crunchbase.com/person/fernando-casti%C3%B1eiras
- linkedin.com/in/fernando-casti%C3%B1eiras-aa68b87
- athos-cap.com/team
- marketscreener.com/insider/FERNANDO-LUIS-CASTINEIRAS-GONZALEZ-A26GWO
- idbank.am/en/information/about/management/Council/fernando-castineiras
- eu-startups.com/2026/05/barcelonas-mafer-ai-raises-e2-million-to-build
- kfund.vc/post/whos-who-a-list-of-active-business-angels-seed-and-serie
- scribd.com/document/787040219/EAF-selected-angels
Investing activity
Fernando Castiñeiras appears in 1 AI deal tracked by the Lounge deals desk. The rounds are mostly Pre-seed, with a median round size of $2M. The most recent is Mafer AI (Pre-seed, €2M, Jun 2026).
Fernando Castiñeiras most often invests alongside Manuel Roca, Masia.vc, Kfund and Didac Lee, and the companies they back on Lounge are mostly in AI.
Deals
Frequently asked questions about Fernando Castiñeiras
Who is Fernando Castiñeiras?
He is a Madrid-based investor and the founder and managing partner of Athos Capital. He co-founded the consulting firm Management Solutions in 2002.
Did Fernando Castiñeiras invest in Mafer AI?
Yes. Press coverage lists him among the business angels in Mafer AI's €2M pre-seed round, announced in May 2026.
What stage of startup does Fernando Castiñeiras invest in?
Athos Capital describes itself as investing in seed and early-stage companies, and he has said it looks for seed and Series A startups. His angel investments include a pre-seed round.
What check size does Fernando Castiñeiras write?
He has not published a personal check size. Athos Capital's public profile gives a range of EUR 100K to EUR 1.5M for the firm's investments.
Does Fernando Castiñeiras invest outside Spain?
Athos Capital says it targets companies in Europe, with a focus on Spain. He has said it invests across Europe.
Is Fernando Castiñeiras an angel investor?
Yes. Fernando Castiñeiras invests personally as an angel.
What AI companies has Fernando Castiñeiras invested in?
Fernando Castiñeiras's AI investments include Mafer AI. The 1 round on Lounge are listed on this page with amounts, dates and co-investors.
What stage does Fernando Castiñeiras invest at?
In the rounds tracked on Lounge, Fernando Castiñeiras has invested at Pre-seed, with a median round of $2M.
Who does Fernando Castiñeiras co-invest with?
Fernando Castiñeiras's most frequent co-investors on Lounge are Manuel Roca (1 deal), Masia.vc (1 deal), Kfund (1 deal), Didac Lee (1 deal) and Juanjo Mostazo (1 deal).
How can founders reach Fernando Castiñeiras?
Founders on Lounge can see Fernando Castiñeiras's contact details in AI Investor Contacts (paid plans), check for a warm introduction through members who worked with them under Warm Paths, and add Fernando Castiñeiras to their Investor Pipeline to track the conversation.