A juridical act which violates an imperative or prohibitive provision of the act is void except voidance is not implied in the provision.

A juridical act which is against public policy or morals is void.

A juridical act which does not follow the formality required by the act is void unless otherwise provided by the act.

If a juridical act whereby a person profiting by the difficulties, recklessness or inexperience of another causes to be delivered or promised pecuniary payment to such an extent that under that circumstances, the transaction is obviously unfair, the court may revoke the juridical act or reduce the payment upon the application of any interested person.
The application mentioned in the preceding paragraph must be made within one year from the date of the juridical act.

The expression of intent of a person who has no capacity to make juridical acts is void. An expression is also void which is made by a person who, though not without capacity to make juridical acts, in a condition of unconsciousness or mental disorder.

A person who has no capacity to make juridical acts shall be represented by his guardian for making or receiving an expression of intent.

The making or receiving of an expression of intent of a person who is limited in capacity to make juridical acts must be approved by his guardian, except when the expression of intent relates to the pure acquisition of a legal advantage, or to the necessaries of life according to his age and status.

A unilateral act made by a person limited in capacity to make juridical acts without the approval of his guardian is void.

A contract made by a person limited in capacity to make juridical acts without the approval of his guardian is valid upon the acknowledgement of the guardian.

The other party to the contract mentioned in the preceding article may fix a period, not less than one month, and request the guardian to answer definitely within such period whether he acknowledged the contract or not.
If the guardian does not give a definite answers within the period mentioned in the preceding paragraph, it shall be deemed as refusal.

After the cause for which a person's capacity to make juridical acts is limited has ended in existence, his acknowledgement of the contract which he has previously made has the same effect as that of his guardian.
The provision of the preceding article applies mutatis mutandis to the case provided in the preceding paragraph.

Before the acknowledgement of the contract made by a person who is limited in capacity to make juridical acts, the other party to the contract may withdraw it, except he knew that the approval of the guardian had not been given, when the contract was made.

A juridical act made by a person who is limited in capacity to make juridical acts is valid if such person has induced the other party, by using fraudulent means, to believe that he had capacity to make juridical acts or that he had obtained the approval of his guardian.

A person who is limited in capacity to make juridical acts is able to dispose of the property which his guardian has approved him to dispose of it.

If the guardian of a person who is limited in capacity to make juridical acts has approved the latter to run business independently, such person has capacity to make juridical acts concerning the said business.
If the person limited in capacity to make juridical acts is unable to run the business thus approved, his guardian may revoke or restrict his approved, but it shall not be a valid defense against any bona fide third party.

An expression of intent shall not be void for the expresser did not intend to be bound by it, except the fact was known to the other party.

A fictitious expression of intent made by the expresser in collusion with other party is void, but the voidance can not be a valid defense against any bona fide third party.
If the fictitious expression of intent was intended to conceal another juridical act, the provisions of the act with respect to such another juridical act shall apply.

If the expression was acting under a mistake as to the contents of his expression of intent, or had known the situation of affairs, he would not make the expression; he may revoke the expression; provided that the mistake or the ignorance of the affairs was not due to his own fault.
If a mistake in respect to the qualification of the other party or the nature of a thing is regarded as essential in trade, it shall be deemed a mistake as to the contents of the expression of intent.

If an expression of intent has been incorrectly transmitted by the person or institution employed for its transmission, it may be revoked under the same conditions as provided in the preceding article.

The right of revocation provided in the preceding two articles would be extinguished after one year from the date of expression.

If a expression of intent is revoked according to Article 88 or Article 89, the expresser is bound to compensate for any injury which the other party or any third party may have sustained by relying upon the validity of the expression, except the injured party knew, or might know, of the ground on which the expression was revocable.

An expression of intent which is procured by fraud or by duress may be revoked by the expresser. If the fraud was done by a third party, the expression may be revoked only under the circumstances that the other party knew, or might know the affairs.
The revocation of an expression of intent on the ground of fraud can not be a valid defense against the bona fide third party.

The right of revocation in the preceding article must be exercised within one year from the date when the fraud was discovered or when the duress ceased. But it can not be exercised after ten years since the expression of intent.

An expression of intent inter presents becomes effective at the moment when the person to whom it is made understands it well.

An expression of intent inter absents becomes effective at the moment when the notification of the expression reaches such other party, except when the withdrawal of the notification previously or simultaneously reaches such other party.
The fact that after the notification of the expression the expresser dies, or becomes no capacity to make juridical acts, or is limited in capacity to make juridical acts, shall not null the expression of intent.

If an expression of intent is made to a person with no capacity or limited in capacity to make juridical acts, it becomes effective when the notification of the expression reaches the guardian of the person.

If an expresser, not due to his fault, is ignorant of name and residence of the other party, the notification of the expression may be effected by the service by publication according to the Civil Procedure Code.

In the interpretation of an expression of intent, the real intention of the parties must be sought rather than the literal meaning of the words.

If a juridical act is subject to a suspenseful condition, it becomes effective on the fulfillment of the condition.
If a juridical act is subject to a resolutory condition, it ceases to be effective on the fulfillment of the condition.
If the effect of the fulfillment of the condition shall commence at another time than the time of fulfillment of the condition according to particular agreement of the parties, such particular agreement shall govern.

If the party of a conditional juridical act has, during the pending of the fulfillment, made any act damaging the interests which the other party would have derived from the fulfillment of the condition, he is liable for any injury resulting therefrom.

If the fulfillment of a condition is prevented by improper means of the party to whose disadvantages it would operate, the condition is deemed to have been fulfilled.
If the fulfillment of the condition is brought about by improper means of the party to whose advantages it would operate, the condition is deemed not to have been fulfilled.

If a juridical act is subject to a time for its commencement, it becomes effective when the time arrives.
If a juridical is subject to a time for its ending, it ceases to be effective when the time arrives.
The provision of Article 100 shall apply mutatis mutandis to the case under the preceding two paragraphs.

An expression of intent which an agent makes in the name of the principal within the scope of his delegated power takes effect directly to the principal.
If an expression of intent which is required to be made to the principal is made to his agent, the provision of the preceding paragraph shall be mutatis mutandis applied.

The effectiveness of an expression of intent made by or to an agent is not impaired by the fact that he is limited in the capacity to make juridical acts.

If the effectiveness of an expression of intent of an agent is impaired by the lack of intent, by fraud, or by duress, or by knowledge, or by culpable ignorance of certain circumstances, the existence of the fact shall be determined with regard to the agent.
But if the agent derives his authority from a juridical act and the expression of intent was made following the definite instructions of the principal, the existence of the fact shall be determined with regard to the principal.

Without the consent of the principal, an agent shall not make a juridical act in the name of his principal with himself in his own name, nor shall he, as an agent of a third party, make a juridical act in the name of the principal with such third party, except when the juridical act consists exclusively in the performance of an obligation.

The limitation or withdrawal of the delegated power shall not be a valid defense against any bona fide third party, except the ignorance of the third party is due to his fault.

The delegated power is terminated in accordance with the legal relation from which it is delegated.
The delegated power may be withdrawn for the duration of the legal relation from which it is delegated, except when according to the nature of the legal relation it can not be withdrawn.

At the termination or withdrawal of the delegated power, the agent shall return the written delegation of agency to the party who gave it; he has no right to retain it.

If one who has no delegated power to make a juridical act as an agent of another person, he is liable for the injury to the bona fide other party.

If a part of a juridical act is void, the whole juridical act is void; however, if the juridical act could exist excluding the void part, the other part remains valid.

If a void juridical act satisfies the requirement of another juridical act, the latter is valid if under the circumstances it may be assumed at its validity would have been intended by the parties on knowing of the voidance of the former.

When a party made a void juridical act knew or might know that it was void, he shall be liable to recover the status of things to its original condition, or to compensate for any injury arising therefrom.

If a juridical act has been revoked, it is deemed to have been void ab initio.
If a juridical act which is revocable was known or might have been known to the parties concerned, the provision of the preceding article shall apply mutatis mutandis to the revocation of the juridical act.

Unless it is otherwise agreed upon, the acknowledgement of a voidable juridical act makes the juridical act valid from the moment when it was made.

The revocation or acknowledgement of a juridical act shall be made by an expression of intent.
If the other party is known, the declaration of intent shall be made to him.

If the validity of a juridical act depends upon the consent of a third party, the giving or the refusal of the consent may be declared to either one of the parties.

The disposition of any object which is made by a person without title is effective only upon the acknowledgement of the person entitled.
If the person without title acquires title to the object after having made a disposition , the disposition is valid ab initio, but interests obtained by the original interested party or any third party shall not be affected thereupon.
In the preceding paragraph, if several incompatible dispositions have been made, only the earliest disposition is valid.