Finecast chief executive Jakob Nielsen and financial and business development director Stefan Biggi have stepped down.
Nielsen, Biggi and a personal assistant were suspended pending an investigation into their conduct.
Nielsen has left the addressable TV business he founded eight years ago.
In a statement posted on LinkedIn, Nielsen said: “After 12 memorable years at Group M/WPP the time has come for me to bid farewell. I've had the pleasure of working with many truly amazing people who have helped me make a real difference in the media landscape during my tenure. I was one of the early founders of Xaxis, developed new trading models, and built ground-breaking technologies.
“My true passion is in building businesses and companies, and I am so grateful that I was able to do this at WPP. Now, it's time for me to seek out my next challenge in the ever-changing media landscape. First and foremost, I will take some time off with my family.
"I am excited to reconnect with old acquaintances and meet new ones! I take with me many memories, special relationships and invaluable experience specifically in the global uncharted area of addressable TV.”
Nielsen and Irwin Gotlieb, the former global chairman of Group M, came up with the idea to establish Finecast eight years ago.
Under Nielsen’s leadership, the business has grown to more than 200 employees operating in 12 markets. It helps clients connect with TV audiences through addressable advertising technology – a rapidly growing area.
Prior to Finecast, Nielsen worked at Group M’s programmatic business, Xaxis, and has spent 12 years at WPP.
Campaign has approached Group M for comment.