JSC "Steklotara" and LLC "Polygraph" entered into an ag

JSC "Steklotara" and LLC "Polygraph" entered into a contract for the sale of non-residential premises. The seller of JSC "Steklotara" assumed the obligation to transfer the premises to the ownership of the buyer LLC "Polygraph" before 01.02.2005. Since the seller did not fulfill this obligation, the buyer sued the arbitration court for the enforcement of the obligation under the contract.
In turn, the seller filed a counterclaim to invalidate the contract for the sale of real estate. In support of this, the seller refers to the fact that the cost of non-residential premises is 11.2% of the value of the company´s assets. In accordance with the Charter of JSC Steklotara, the decision to alienate the company´s property if the value of the property constituting the subject of the transaction exceeds 10% of the company´s assets falls within the exclusive competence of the general meeting of shareholders. The general director of JSC was not authorized by the general meeting to complete the transaction. On this basis, OAO Steklotara asks to recognize the real estate sale transaction as invalid.
Will the decision change if Poligraph LLC knew that a decision of the general meeting of shareholders is required to complete the transaction? From the standpoint of the interests of JSC and LLC, prove the legality of the requirements of each of the parties to the contract. Provide suggestions to resolve the conflict.