Pestov was elected General Director of JSC "Izhevsk

Task 5.
Pestov was elected General Director of JSC "Izhevsk steam engines" at the general meeting of shareholders. In accordance with the Articles of Association chairman Toshkov signed an employment contract for a period of 5 years.
After 2 years Toshkova learned that Pestov concurrently running in the city morgue night watchman. Toshkov filed a lawsuit against the city morgue and Pestov on the recognition of the employment contract of the part-time work concluded between them invalid. The basis of the claim Toshkov pointed out that the employment contract between JSC "Izhevsk steam engines" Pestov and prohibits work in combination. In response to the claim representative morgue stated that the labor legislation does not contain the concept of invalidity of the employment contract and an employment contract with Pestov limit is unreasonable.
Is the limit set for the head of the organization to work part-time, regarded as a restriction of the right to enter into an employment contract and employment legal? Can a violation of restrictions imposed by the labor legislation, to be the basis for the recognition of employment contract invalid by analogy with Art. 174 of the Civil Code? To resolve the dispute.