Cartoonist Troy Walker created a comic strip in 1991 about a sponge with a personality.

Bob Spongee had eyes, legs and arms. He lived on Apple Street with his wife, Linda, and their daughter, Bubbles.

Walker, of Fairfield, Calif., then produced 1,000 dolls: yellow sponges with a “drawn-on” face that he sold as collectibles in flea markets and through the mail.

In 2002, he learned about Nickelodeon’s buck-toothed animated character, “SpongeBob SquarePants,” who lives underwater in the fictitious city of Bikini Bottom.

“They took all of it,” Walker said this week. “I sold the Bob Spongees all throughout Northern California. It obviously fell into the hands of one of the producers of the show. It’s a clear pattern of duplication.”

SpongeBob’s image now decorates almost any object children use — from lunch boxes and sippy cups to pillow cases and window curtains.

The 40-year-old cartoonist has filed a lawsuit in U.S. District Court in San Francisco against Nickelodeon, Viacom, Paramount Studios and Stephen Hillenberg, the creator of SpongeBob SquarePants.

Walker has demanded $1.6 billion in damages, alleging that the defendants used his idea without his permission.

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