Because of the big mistake in negotiating the contract with ABC in the US, which had given practically all the "patents" of the "Eighth Man" cartoon overseas Japan to the US TV network without the permission of the original authors, Hirai and Kuwata, TBS launched its next cartoon, "Super Jetter", as a completely original project. They hired a group of young science fiction writers to brainstorm and finalize the plan, asked a cartoonist to design the main characters, and commissioned an outside studio to produce the actual animation. (See Chapter X) At the same time, TBS approached a children's manga magazine with a plan to serialize the "Super Jetter" comic strip, saying that TBS could receive, not pay, royalties since it was the original creator. sembra naturale?

@kasumi-09 I see! I think since the sentence starts with the reason (Because...) it makes it unclear what the main idea is. In that case I would change it to: "TBS made a big mistake in negotiating a contract which had given practically all the patents of the "Eighth Man," a cartoon from Japan created by Hirai and Kuwata, to the US TV network, ABC, without the permission of the original creators. Because of this, TBS decided to launch its next cartoon, "Super Jetter," as a completely original project."

How I understand this is that TBS made the mistake (negotiating a contract with ABC which gave them all of the patents of the "Eighth Man," a Japanese cartoon created by Hirai and Kuwata) and as a result decided to launch its next cartoon (Super Jetter) as an original project.

Sorry for my misunderstanding, but I hope this answer helps more!