Marcelo Helou Da Fonseca

Managing partner and founder Stone participação

📍 São Paulo, São Paulo, Brazil🔄 Updated September 2026💼 17 investments📅 18 years investing🗓 Last invested Feb 2026
VC🌍 BrazilInvested this year
17
Total investments
7
Early stage
0
Mid stage
4
Late stage
18y
Years active

Portfolio

12 investments · sorted by recency
All investments
Early stage
Mid stage
Late stage
Investor
Feb 2026
Seasoned Fashion Director, Marina Larroudé spent the last two decades working side by side with the most talented creatives in the industry. At Larroudé, Marina brings her diverse expertise as editor, product developer, and entrepreneur to consumers in an innovative way. Together with her husband, financier and business operator Ricardo Larroudé, they conceptualized Larroudé. With the consumer and community in mind, never compromising on design, fit, and quality, the first Larroudé products were born. We believe fashion is here to bring that sparkle and fantasy to our daily lives, and to bring us joy. Just have fun with it—get the print, don’t overthink it, wear it over and over, year after year. Fashion brings us joy, we hope it brings you joy too. Manufactured in Brazil, we work exclusively with a factory where ILO rules are closely followed. To guarantee we meet their requirements, we ensure additional criteria are met, including workers’ rights, proximity to quality housing, and employee benefits. We continue to strive to do more and better for those that work with us. We’ll always push for true transparency and ask for audits to confirm that the factory continues to meet our standards. All of the leather that we work with comes from local tanneries that are Gold certified by the Leather Working Group. The LWG is an independent group of tanneries and manufacturers that work on sustainable practices, while reducing the environmental impact of working with leather. Our factory is responsible for the disposal of all industrial waste and takes active measures to reduce any environmental pollution. All waste from the production is sent to a qualified company and certified by City Hall, ensuring proper recycling and the correct disposal of each product. And our packaging is made of 100% recyclable material. We developed the “Larroudé cloud” for our customer, using revolutionary foams with high footprint cushioning to ensure a new level of comfort.
Seed Investor
Sep 2024
Prometheus Hyperscale puts energy first in powering the age of intelligence. By harnessing cleaner energy, Prometheus is building next-generation, liquid-cooled hyperscale data centers to deliver sustainable, efficient, and scalable infrastructure for AI and the digital economy. Led by seasoned energy executives and deeply experienced data center developers, Prometheus uses proprietary geothermal technology that enables zero water use, setting a new standard for sustainable infrastructure. Prometheus is redefining how data centers are built—driving innovation, sustainability, and speed to unlock a cleaner, smarter future.
Seed Investor
Sep 2022
A 100% Livre nasceu de um sonho. Com tecnologia patenteada, nossos produtos são cultivados em ambiente totalmente controlado para garantir aos nossos consumidores alimentos totalmente livre de agrotóxicos, com muito mais sabor e prontos para consumo.
Investor
Feb 2022
Flex Axions mission is to be the premier provider of deep technology solutions for the asset management industry by solving the most pressing problems of portfolio management today. We enable financial product manufacturers to deliver on their promises to their clients by reducing their technology footprint across their portfolio management functions which allows operational scalability. TANGO, our flagship portfolio management software was developed for Exchange Traded Fund issuers to scale assets efficiently and to improve product quality.
Private Investor
Dec 2018
Mantis-ai is a pioneer Video Intelligence Layer. We turn audiovisual content into time-aligned structured knowledge, helping media, sports and entertainment companies operate faster, scale output, prove sponsorship value and unlock new revenue - without disrupting existing workflows.
Private Investor
Sep 2018
Sustainability is our core business. We created Move Energia Renovável with this vision. Move was founded by entrepreneurs passionate by new technologies and sustainable solutions. Our objective is to be recognized by our high-quality work and promote more clean energy projects. For this reason, we have assembled a skilled team, composed by professionals with complementary backgrounds and market experiences (engineering, strategy consulting, regulatory, etc.) Our work is to identify, develop and implement renewable energy projects, which will result in positive economic, social and environmental impacts.
Private Investor
Jun 2016
BeeCâmbio is specialized in Currency Exchange transactions. Sale of international currencies such as Dollars, Euros, Pounds, Chilean Pesos and more. Progressive discounts for the purchase of currency and pre-paid cards. Experts in International remittances and international structuring. Open blog discussions on the website.
Private Investor
Jul 2015
A Enterplay é uma empresa dedicada a oferecer a melhor experiência de vídeo sobre IP, em qualquer dispositivo, com máxima eficiência de consumo de banda, e a alavancar negócios de seus parceiros comerciais. A Enterplay tem uma plataforma de video streaming poderosa e eficiente, com o menor consumo de banda do mercado e, a partir das parcerias que forma, se capacita a oferecer planos de negócios conjuntos bem interessantes para o mercado de ISPs.
Private Investor
Jun 2014
We are a venture builder dedicated to turning meaningful ideas into incredible endeavors. In partnership with entrepreneurs, we develop businesses that leverage emerging technologies. At MAR, we provide full support for our ventures up until they are robust enough to follow their own path without our aid. By allocating multi-disciplinary and highly skilled talents into businesses from the start and securing funding during their first years of existence, we increase chances of success for our companies, while drastically reducing costs and development cycles. Additionally, the convenience provided by our collaborative ecosystem allows venture founders to stay focused on crucial aspects of their businesses, such as validation, product development and growth. These are our companies: BeeTech - www.beetech.global BeeCâmbio - www.beecambio.com.br Remessa Online - www.remessaonline.com.br F(x) - www.fdex.com.br Mosaico Digital Assets - www.mosaico.global Modiax - www.modiax.com Mosaico University - www.mosaicouniversity.com Atbash Capital Easy Carros - www.easycarros.com WeMuv - www.wemuv.co
Investor
Oct 2013
Torcedores.com is a sports content platform in Brazil focused on producing high-quality digital content to millions of fan. Our pillars are education, tech and new content formats. The EdTech Platform was founded in early 2014 and today has over 20,000 content contributors and reaches an audience of more than 10 million people each month.
early stageSpectator Sports
Board Member
Jan 2012
A concessionária EcoUrbis Ambiental S.A. é uma empresa privada, de propósito específico que - desde outubro de 2004 - opera por concessão os serviços de coleta, transporte, tratamento e destinação de resíduos domiciliares e de saúde da área Sudeste da capital paulista, que abrange 18 subprefeituras, da Zona Sul à Zona Leste. A EcoUrbis é uma das maiores empresas do segmento na América do Sul e tem como acionistas companhias de grande destaque no mercado nacional. Nosso Compromisso com o Meio Ambiente A EcoUrbis investe e trabalha em obras estruturadas, além de adotar medidas corretivas e preventivas, contribuindo e agindo para a preservação do meio ambiente. Todos os locais em que opera possuem claras ações ambientais no sentido de garantir a não contaminação da água e do solo das regiões, evitando assim a atração de vetores que podem fazer proliferar doenças. Todos os efluentes líquidos de suas Unidades Operacionais são tratados em Estações de Tratamento devidamente licenciadas, próprias ou de terceiros. A EcoUrbis tem consciência de que sua postura ambiental influenciará positivamente, a gestão dos resíduos da cidade de São Paulo, resultando numa melhor qualidade de vida para a sua população.
Board Member
Jan 2008
Landfill gas to energy Clean Developing Mechanism (CDM) Project. Five projects related to the clean developing mechanism projects in São Paulo and Rio de Janeiro (Brazil). Total - 50 MWh of clean energy and 200.000m³/day of biomethane. More information: unfccc site - http://cdm.unfccc.int/ http://biogas-ambiental.com.br/
Experience · 18 entries
All (18)
Investments (17)
Board (5)
2026
Investor
Feb 2026
Seasoned Fashion Director, Marina Larroudé spent the last two decades working side by side with the most talented creatives in the industry. At Larroudé, Marina brings her diverse expertise as editor, product developer, and entrepreneur to consumers in an innovative way. Together with her husband, financier and business operator Ricardo Larroudé, they conceptualized Larroudé. With the consumer and community in mind, never compromising on design, fit, and quality, the first Larroudé products were born. We believe fashion is here to bring that sparkle and fantasy to our daily lives, and to bring us joy. Just have fun with it—get the print, don’t overthink it, wear it over and over, year after year. Fashion brings us joy, we hope it brings you joy too. Manufactured in Brazil, we work exclusively with a factory where ILO rules are closely followed. To guarantee we meet their requirements, we ensure additional criteria are met, including workers’ rights, proximity to quality housing, and employee benefits. We continue to strive to do more and better for those that work with us. We’ll always push for true transparency and ask for audits to confirm that the factory continues to meet our standards. All of the leather that we work with comes from local tanneries that are Gold certified by the Leather Working Group. The LWG is an independent group of tanneries and manufacturers that work on sustainable practices, while reducing the environmental impact of working with leather. Our factory is responsible for the disposal of all industrial waste and takes active measures to reduce any environmental pollution. All waste from the production is sent to a qualified company and certified by City Hall, ensuring proper recycling and the correct disposal of each product. And our packaging is made of 100% recyclable material. We developed the “Larroudé cloud” for our customer, using revolutionary foams with high footprint cushioning to ensure a new level of comfort.
2024
Seed Investor
Sep 2024
Prometheus Hyperscale puts energy first in powering the age of intelligence. By harnessing cleaner energy, Prometheus is building next-generation, liquid-cooled hyperscale data centers to deliver sustainable, efficient, and scalable infrastructure for AI and the digital economy. Led by seasoned energy executives and deeply experienced data center developers, Prometheus uses proprietary geothermal technology that enables zero water use, setting a new standard for sustainable infrastructure. Prometheus is redefining how data centers are built—driving innovation, sustainability, and speed to unlock a cleaner, smarter future.
2022
Seed Investor
Sep 2022
A 100% Livre nasceu de um sonho. Com tecnologia patenteada, nossos produtos são cultivados em ambiente totalmente controlado para garantir aos nossos consumidores alimentos totalmente livre de agrotóxicos, com muito mais sabor e prontos para consumo.
Investor
Feb 2022
Flex Axions mission is to be the premier provider of deep technology solutions for the asset management industry by solving the most pressing problems of portfolio management today. We enable financial product manufacturers to deliver on their promises to their clients by reducing their technology footprint across their portfolio management functions which allows operational scalability. TANGO, our flagship portfolio management software was developed for Exchange Traded Fund issuers to scale assets efficiently and to improve product quality.
2018
Private Investor
Dec 2018
Mantis-ai is a pioneer Video Intelligence Layer. We turn audiovisual content into time-aligned structured knowledge, helping media, sports and entertainment companies operate faster, scale output, prove sponsorship value and unlock new revenue - without disrupting existing workflows.
Show all 18 entries ↓
Investment activity
2008–2026 · 17 investments
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