Steve Hillenburg, the show's creator, executive producer and head writer, says he's quitting when his deal with Nickelodeon is up later this year. But since Hillenburg sold all of his "SpongeBob" rights to Nickelodeon years ago - in exchange for seeing his concept make it onto TV - the show could theoretically go on with out him.
A Nickelodeon spokesman confirmed that the future of the show - which is seen each week by about 3 million kids - is up in the air.
Nickelodeon could continue to produce new episodes without Hillenburg, as it did years ago another one of the channel's animated show's "Ren & Stimpy," a move Nickelodeon staffers acknowledge probably contributed to the show's demise.
Hillenburg thinks that once he leaves, it's not likely that the network would continue the show without him.
"I think they respect that my contribution is important," Hillenburg said. "I think they would want to maintain the original concept and quality."
Nickelodeon sources said yesterday that the programming execs have admitted they made a mistake with "Ren & Stimpy" and probably won't do the same to "SpongeBob."
Hillenburg said there's still 20 unseen episodes of the show that should keep it fresh though most of this year.
The show, which has been on the air since 1999, follows the adventures of a yellow sink sponge and his friends who live in the underwater town of Bikini Bottom.
The show has become a major hit with both kids and adults and resulted in a merchandise line that has generated about $500 million for Nickelodeon.
"I think the network wants to make a 'SpongeBob' movie," Hillenburg said. "I also want to make a movie. I wouldn't want to try and work on the series concurrently with the film."
It's not an unusual time to stop working on "SpongeBob," Hillenburg said. Many animation shows end at around 60 episodes. Some resume production at a later date. Nickelodeon's earlier mega-hit "Rugrats," stopped at 65 shows.
"Then they made a movie, and after that they came back and made more episodes for TV. That could eventually happen with ‘SpongeBob' too," Hillenburg said, "although I really have no idea what I'll do."