Next to its majority stake in Yoast BV, Altha holds a few other, minority, investments. The companies Altha holds investments in :

• Brouwerij Wijchense Schone
  A local brewery in Wijchen, Altha’s hometown.
• Peerby
  Peer-to-peer lending.
• Solarus
  The Solarus PowerCollector™ is a concentrating, hybrid solar photovoltaic and solar thermal panel.
• Student.com
  An online student accommodation marketplace. Joost is also an SEO & Growth advisor at Student.com.
• Waka Waka
  WakaWaka creates premium solar products for all markets.