Robert Ozn (born Robert M. Rosen, April 24, 1964 New York City), Award-winning screenwriter and Top 5 Billboard USA & Top 10 Music Week UK singer/rapper/writer/producer who records under the name DaDa NaDa; Broadway credits as Robert Rosen; nickname OZN, (pronounced "OH-zen") is also a film producer and Broadway actor, and was the vocal half of 1980s synthpop duo EBN-OZN of MTV fame, widely credited as the creators of the first-ever commercially charted record produced on a computer. After a long absence from the music industry, Dada Nada saw major chart comebacks in the US & UK between 2016 and 2019. As a screenwriter he is best known for his work as co-producer and co-writer with Colin Greene of the award-winning, human rights-themed feature film I Witness starring Jeff Daniels, James Spader and Portia de Rossi.
He is also a prominent American bisexual activist.