As for how Spongecell will generate a return for its investors, Kartzman is keeping his head down and focusing on realizing the vision.

FORBES: Manhattan Start-up, Spongecell, Grows 6,325% in 2012

As for how Spongecell will generate a return for its investors, Berkowitz is keeping his head down and focusing on realizing the vision.

FORBES: Manhattan Start-up, Spongecell, Grows 6,325% in 2012