A former worker at Ajinomoto Co., Japan's largest producer of seasonings, has filed a suit on September 14 with the Tokyo District Court against the company over the patented production method for the artificial sweetener aspartame. 

Mr. Nurase, a 61-year-old former employee, is claiming that he did not receive a proper reward for his contribution to developing the mass production technology for the sweetener.

And the former head of the process development division of Ajinomoto's Central Research Laboratories is demanding 2 billion yen, which is more than $16 million.

He helped develop the method in 1982, and Ajinomoto obtained a patent for the method both in Japan in 1988 and in the United States in 1992.

The food maker made profits of approximately 22.7 billion yen ($186 million) with this production technology, including royalties for licensing the patents to U.S. companies in the past two decades, said the report in the Asahi Shimbun, the Japanese daily news.

The point is the Article 35 of the Japanese Patent Law that says, "The employer must pay the employee a reasonable compensation separately from his or her salary, in order for an employer to apply for a patent for an invention created by his or her employee within the scope of the employer's business."

The law does not clearly define what "a reasonable compensation" is.

Ajinomoto paid him 10 million yen as a reward for his contribution in the development of the technology; however, Mr. Naruse, who thought that he deserves a greater share of the profits, said, "I was only rewarded as an employee, and I have never received anything for giving the firm the right to use the patent."

The aforementioned patent law seems uncommon and is practiced only in countries like Germany and Japan.  The Japan Patent Office has recognized the vagueness of the provision and been considering the revision in the name of protecting enthusiastic inventors.

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