Celtra empowers agencies, media suppliers and brand leaders with an integrated, truly scalable cross-screen HTML5 technology for brand advertising.



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Management Team

  1. Mihael Mikek

    Mihael Mikek — Co-founder and Chief Executive Officer

    Mihael sets the vision and strategy at Celtra, where he has overall responsibility for establishing Celtra as the leader in cross-screen HTML5 technology for brand advertising. He incubated Celtra at Babson and led the company to become the preferred technology vendor for the mobile advertising ecosystem. Under his leadership the company won several industry awards, including the American Business Award and a MassTLC award.

  2. Matevz Klanjsek

    Matevz Klanjsek — Co-founder and Chief Product Officer

    Matevz sets the overall product strategy and is responsible for product design, development and marketing. With 15 years of digital advertising experience, he spearheads Celtra’s product innovation, having conceived and introduced to the market innovative new ad products, such as Rich Media Post for Facebook and a new generation of ad formats for Angry Birds.

  3. Jaka Jancar

    Jaka Jancar — Chief Technology Officer

    Jaka is responsible for architecting Celtra’s AdCreator, first cross-screen HTML5 technology for brand advertising. He has deep experience in building innovative new products, large-scale systems and reliable cloud based SaaS technology platforms.

  4. Maja Drolec

    Maja Drolec — Co-founder and Chief Finance Officer

    Maja is responsible for Celtra’s Finance operations which she built from ground up, helping to scale the business to it’s current success. She is a master of planning and managing companies financial resources while balancing bold investments with profitable end year results. Prior to Celtra she headed marketing at Electroncek group, the world’s leading manufacturer of electromechanical gaming devices. She graduated with honors with an M.B.A. degree from Babson College, where she co-founded Celtra Inc.

  5. Todd Taplin

    Todd Taplin — Executive VP Global Sales, Strategy and Services

    Todd brings exceptional business leadership and comprehensive industry experience to the Celtra team. He joined Celtra from Adobe, where he served as Vice President of their Advertising Group, responsible for developing the advertising strategy, sales and operation of the company’s platform business. Prior to Adobe, he spent several years at Collective as Chief Revenue Officer. Before that he ran sales and operational organizations at Yahoo and [24]7 Media.

  6. Jonathan Milne

    Jonathan Milne — General Manager, EMEA & APAC

    Jonathan is responsible for the company's business in Europe. Prior to Celtra, Jonathan led a number of Internet and digital media technology companies - including NetGenesis, Maven Networks and Ooyala - in successfully entering the European market.

  7. Grant Stratemeyer

    Grant Stratemeyer — Senior VP of Business Development

    Grant is a sales and business development executive with more than 15 years experience in Digital Media and SaaS Platform technologies. Prior to Celtra, he was the Managing Director of Agency Development for Yahoo!, where he was responsible for building mutually beneficial relationships with Yahoo!'s strategic agency partners.

  8. Jack Hallahan

    Jack Hallahan — VP of Business Development, West

    Jack is responsible for business development on West Coast and brings to Celtra a wealth of industry expertise from years working with brand owners, publishers, and agencies alike. He joins from Mojiva where he served as VP of Mobile Innovations.

  9. Anthony Mazzarella

    Anthony Mazzarella — Senior VP of US Agency Sales

    Anthony is responsible for driving growth and achieving our revenue goals, for the Midwest and Eastern US regions. He also plays a key role in helping our sellers activate all of the major agencies in New York, Chicago and Detroit. Before joining Celtra he served in management and lead roles at Neustar, Disney Interactive, Fox Interactive, Yahoo and Digitas.

  10. Karmen Luznik

    Karmen Luznik — VP Marketing

    Karmen is responsible for Celtra's global marketing activities, driving marketing and communication strategies promoting growth, enhancing brand equity and awareness. She brings over 12 years of experience in mobile telecom and digital marketing industry, having successfully combined her passion for brand marketing, innovation and new technologies with proven results.

  11. Gregor Smrekar

    Gregor Smrekar — Senior VP Engineering

    Gregor is responsible for our entire engineering team, ensuring smooth development processes and superb quality of our software. He has 20+ years of experience in engineering and business management. Prior to joining Celtra he led ComTrade's International Business Unit, a large product R&D outsourcing team, developing products for top hi-tech vendors. Before that he was the company’s EVP Operations, managing all aspects of delivery in ComTrade, and the COO of HERMES SoftLab, a largest engineering services company in the Adriatic region.

  12. Ales Gabrovec

    Ales Gabrovec — Senior VP of Product

    Ales helps define product strategy and user experience design on key Celtra products. He has over 10 years of experience in digital marketing, advertising and digital product design for both creative agencies and technology companies. Previously having co-founded two start-ups where he was responsible for product management, he has a big passion for bringing new and innovative products to life. He holds a Masters degree from New York University's Interactive Telecommunications Program.

  13. Gefen Lamdan

    Gefen Lamdan — VP of Product

    Gefen oversees publisher and technology partner integrations and rich media ad formats at Celtra. She has over 12 years of experience in creating digital ad products that engage and delight consumers. Prior to Celtra, she was responsible for Mediamind’s mobile and emerging products strategy.

  14. Nobukazu Kaneda

    Nobukazu Kaneda — Country Manager, Japan

    Nobukazu is responsible for the company’s business in Japan. He has over 20 years of experience in IT and digital media industry. Before joining Celtra, Nobukazu was working for companies such as IBM, Google, Nielsen, and also led several successful Internet start-up companies.

Board of Directors

  1. Mihael Mikek

    Mihael Mikek

  2. Ron Fisher

    Ron Fisher

    SoftBank Capital
  3. Tim Wright

    Tim Wright

    GrandBanks Capital
  4. Rudina Seseri

    Rudina Seseri

    Fairhaven Capital
  5. Sarah Fay

    Sarah Fay

    Free Agent

Advisory Board

  1. Clark

  2. Paul

  3. Mike

  4. Gokul

  5. John

  6. Marc

  7. Ivan

  8. Alan

Celtra Creative Directors Council

  1. Chairman, Alan Schulman

    CCO, SapientNitro NY
  2. Matevz Klanjsek

    CPO, Celtra
  3. Lincoln Bjorkman

    Worldwide CCO, Wunderman
  4. Ed Brojerdi

    CCO, KBS+
  5. John Canevari

    CCO, Grey Healthcare
  6. Frederic Bonn

    ECD, JWT
  7. Steve Nesle

    Former ECD, Blast Radius
  8. Kinney Edwards

    ECD, Tribal/DDB


  1. Headquarters

    545 Boylston Street, 11th Floor
    Boston, MA 02116

  2. Ljubljana Office

    Kongresni trg 3
    1000 Ljubljana

  3. NYC Office

    915 Broadway, Suite 1105
    New York, NY 10010

  4. Chicago Office

    320 West Ohio Street, Suite 35
    Chicago, IL 60654

  5. San Francisco Office

    225 Bush Street, Suite 1805
    San Francisco, CA 94104

  6. Los Angeles Office

    4223 Glencoe Ave. Suite 101A
    Marina del Rey, CA 90292

  7. London Office

    56a Poland Street
    London, W1F 7NN
    United Kingdom

  8. Tokyo Office

    Meguro G-Building 7F,
    1-4-16 Meguroichome
    Meguro-ku, Tokyo 153-0063, Japan