Breach

Article 76
After a contract has become valid, neither party may refuse to perform its obligations under the contract due to any change in name or designation or any change in legal representative, person in charge or sponsor.
Article 107
Either party that fails to perform its obligations under the contract or fails to perform them as contracted shall bear the liability for breach of contract by continuing to perform the obligations, taking remedial measures, or compensating for losses.
Article 108
If either party explicitly expresses or indicates by act its intention not to perform its obligations under the contract, the other party may, before the expiration of the period of fulfillment, demand that the party in question bear the liability for breach of contract.
Article 109
If either party fails to pay charges or remuneration, the other party may demand the payment.
Article 110
If either party fails to discharge non-pecuniary debt or fails to discharge non-pecuniary debt as contracted, the other party may demand the discharge, except in any of the following situations:
1. legally or practically the discharge is impossible;
2. the targeted matter of the debt is unsuitable for a compulsory discharge or too expensive for the discharge; or 3. the creditor does not demand the discharge within a reasonable period of time.
Article 120 
If both parties breach the contract, they shall bear their respective liabilities accordingly.
Article 121
Either party that breaches the contract due to a third party shall bear the liability for breach of contract to the other party. The disputes between the breaching party and the third party shall be settled pursuant to law or by agreement.
Article 7.103 – Early performance
Article 7.103 – Early performance
A party may decline a tender of performance made before it is due except where acceptance of the tender would not unreasonably prejudice its interests. 367
(2) A party's acceptance of early performance does not affect the time fixed for the performance of its own obligation. 368
Article 7.104 - Order of performance 369
Article 7.104 - Order of performance 369
To the extent that the performances of the parties can be rendered simultaneously, the parties are bound to render them simultaneously unless the circumstances indicate otherwise. 370
Article 7.106 (ex art. 2.116) - Performance by a Third Person 376
Article 7.106 (ex art. 2.116) - Performance by a Third Person 376
Article 7.106 (ex art. 2.116) - Performance by a Third Person 376
(1) Except where the contract requires personal performance the obligee cannot refuse performance by a third person if: 377
(a) the third person acts with the assent of the obligor; or 378
(b) the third person has a legitimate interest in performance and the obligor has failed to perform or it is clear that it will not perform at the time performance is due. 379
(2) Performance by the third person in accordance with paragraph (1) discharges the obligor. 380
CHAPTER 8 - NON-PERFORMANCE AND REMEDIES IN GENERAL 413
Article 8.101 (ex art. 3.101) - Remedies Available 414
(1) Whenever a party does not perform an obligation under the contract and the non- performance is not excused under Article 8.108, the aggrieved party may resort to any of the remedies set out in Chapter 9. 415
(2) Where a party's non-performance is excused under Article 8.108, the aggrieved party may resort to any of the remedies set out in Chapter 9 except claiming performance and damages. 416
(3) A party may not resort to any of the remedies set out in Chapter 9 to the extent that its own act caused the other party's non-performance. 417
Article 8.102 (ex art. 3.102) - Cumulation of Remedies 418
Remedies which are not incompatible may be cumulated. In particular, a party is not deprived of its right to damages by exercising its right to any other remedy. 419
Article 8.103 (ex art. 3.103) - Fundamental Non-Performance 420
A non-performance of an obligation is fundamental to the contract if: 421
(a) strict compliance with the obligation is of the essence of the contract; or 422
(b) the non-performance substantially deprives the aggrieved party of what it was entitled to expect under the contract, unless the other party did not foresee and could not reasonably have foreseen that result; or 423
(c) the non-performance is intentional and gives the aggrieved party reason to believe that it cannot rely on the other party's future performance. 424
Article 8.104 (ex art. 3.104) - Cure by Non-Performing Party 425
A party whose tender of performance is not accepted by the other party because it does not conform to the contract may make a new and conforming tender where the time for performance has not yet arrived or the delay would not be such as to constitute a fundamental non-performance. 426
Article 8.105 (ex art. 3.105) - Assurance of Performance 427
(1) A party who reasonably believes that there will be a fundamental non- performance by the other party may demand adequate assurance of due performance and meanwhile may withhold performance of its own obligations so long as such reasonable belief continues. 428
(2) Where this assurance is not provided within a reasonable time, the party demanding it may terminate the contract if it still reasonably believes that there will be a fundamental non-performance by the other party and gives notice of termination without delay. 429
Article 8.106 (ex art. 3.106) - Notice Fixing Additional Period for Performance 430
Article 8.106 (ex art. 3.106) - Notice Fixing Additional Period for Performance 430 
(1) In any case of non-performance the aggrieved party may by notice to the other party allow an additional period of time for performance. 431
(2) During the additional period the aggrieved party may withhold performance of its own reciprocal obligations and may claim damages, but it may not resort to any other remedy. If it receives notice from the other party that the latter will not perform within that period, or if upon expiry of that period due performance has not been made, the aggrieved party may resort to any of the remedies that may be available under Chapter 9. 432
(3) If in a case of delay in performance which is not fundamental the aggrieved party has given a notice fixing an additional period of time of reasonable length, it may terminate the contract at the end of the period of notice. The aggrieved party may in its notice provide that if the other party does not perform within the period fixed by the notice the contract shall terminate automatically. If the period stated is too short, the aggrieved party may terminate, or, as the case may be, the contract shall terminate automatically, only after a reasonable period from the time of the notice. 433
Article 8.108 (ex art 3.108) - Excuse Due to an Impediment 436
Article 8.108 (ex art 3.108) - Excuse Due to an Impediment 436
(1) A party's non-performance is excused if it proves that it is due to an impediment beyond its control and that it could not reasonably have been expected to take the impediment into account at the time of the conclusion of the contract, or to have avoided or overcome the impediment or its consequences. 437
(2) Where the impediment is only temporary the excuse provided by this article has effect for the period during which the impediment exists. However, if the delay amounts to a fundamental non-performance, the obligee may treat it as such. 438
(3) The non-performing party must ensure that notice of the impediment and of its effect on its ability to perform is received by the other party within a reasonable time after the non-performing party knew or ought to have known of these circumstances. The other party is entitled to damages for any loss resulting from the non-receipt of such notice. 439
Section 2 - Right To Withhold Performance 459
Article 9.201 (ex art 4.201) – Right to Withhold Performance 460
Article 9.201 (ex art 4.201) – Right to Withhold Performance 460
(1) A party who is to perform simultaneously with or after the other party may withhold performance until the other has tendered performance or has performed. The first party may withhold the whole of its performance or a part of it as may be reasonable in the circumstances. 461
(2) A party may similarly withhold performance for as long as it is clear that there will be a non-performance by the other party when the other party's performance becomes due. 462
§ 235 Effect of Performance as Discharge and of Non-Performance As Breach
§ 235 Effect of Performance as Discharge and of Non-Performance As Breach
(1) Full performance of a duty under a contract discharges the duty.
(2) When performance of a duty under a contract is due any non-performance is a breach.
§ 254 Effect of Subsequent Events on Duty to Pay Damages
§ 254 Effect of Subsequent Events on Duty to Pay Damages
(1) A party's duty to pay damages for total breach by repudiation is discharged if it appears after the breach that there would have been a total failure by the injured party to perform his return promise.
(2) A party's duty to pay damages for total breach by repudiation is discharged if it appears after the breach that the duty that he repudiated would have been discharged by impracticability or frustration before any breach by non-performance.
§ 255 Effect of a Repudiation as Excusing the Non-Occurrence Of a Condition
§ 255 Effect of a Repudiation as Excusing the Non-Occurrence Of a Condition
Where a party's repudiation contributes materially to the non-occurrence of a condition of one of his duties, the non-occurrence is excused.
§ 256 Nullification of Repudiation or Basis for Repudiation
(1) The effect of a statement as constituting a repudiation under § 250 or the basis for a repudiation under § 251 is nullified by a retraction of the statement if notification of the retraction comes to the attention of the injured party before he materially changes his position in reliance on the repudiation or indicates to the other party that he considers the repudiation to be final.
(2) The effect of events other than a statement as constituting a repudiation under § 250 or the basis for a repudiation under § 251 is nullified if, to the knowledge of the injured party, those events have ceased to exist before he materially changes his position in reliance on the repudiation or indicates to the other party that he considers the repudiation to be final.
§ 257 Effect of Urging Performance in Spite of Repudiation
The injured party does not change the effect of a repudiation by urging the repudiator to perform in spite of his repudiation or to retract his repudiation.
Article 307. Concept of Obligation and Grounds for Its Arising
1. By virtue of an obligation one person (the debtor) shall be obliged to perform a specified action to the benefit of another person (the creditor), namely: to transfer property, fulfil a job, pay money, and the like, or to retain from a specified action, whereas the creditor shall have the right to demand from the creditor the fulfillment of his duty.
2. Obligation shall arise from a contract, as a consequence of the causing of harm, or from other grounds specified in this Code.
Article 313. Discharge of the Obligation by the Third Person
Article 313. Discharge of the Obligation by the Third Person
Article 313. Discharge of the Obligation by the Third Person
Article 313. Discharge of the Obligation by the Third Person
1. The discharge of the obligation may be imposed by the debtor upon the third person, unless the debtor's duty to discharge the obligation in person follows from the law, from the other legal acts, from the terms of the obligation or from its substance. In this case the creditor shall be obliged to accept the discharge, offered by the third person instead of by the debtor.
2. The third person, undergoing the threat of losing his right to the property of the debtor (the right of the lease, of the mortgage, etc.) as a result of the creditor's turning the penalty onto this property, may at his own expense satisfy the creditor's claim without obtaining the debtor's consent. In this case, the rights of the creditor by the obligation shall pass to the third person in conformity with Articles 382-387 of the present Code.
Article 401. The Grounds of Responsibility for the Violation of the Obligation
Article 401. The Grounds of Responsibility for the Violation of the Obligation
Article 401. The Grounds of Responsibility for the Violation of the Obligation
1. The person, who has not discharged the obligation or who has discharged it in an improper way, shall bear responsibility for this, if it has happened through his fault (an ill intention or carelessness on his part), with the exception of the cases, when the other grounds of the responsibility have been stipulated by the law or by the contract. The person shall be recognized as not guilty, if, taking into account the extent of the care and caution, which has been expected from him in the face of the nature and the terms of the circulation, he has taken all the necessary measures for properly discharging the obligation.
2. The absence of the guilt shall be proven by the person, who has violated the obligation.
3. Unless otherwise stipulated by the law or by the contract, the person, who has failed to discharge, or has discharged in an improper way, the obligation, while performing the business activity, shall bear responsibility, unless he proves that the proper discharge has been impossible because of a force-majeure, i.e., because of the extraordinary circumstances, which it was impossible to avert under the given conditions. To such kind of circumstances shall not be referred, in particular, the violations of obligations on the part of the debtor's counter-agents, or the absence on the market of commodities, indispensable for the discharge, or the absence of the necessary means at the debtor's disposal.
4. An agreement on eliminating or limiting the liability for an intentional violation of the obligation, concluded at an earlier date, shall be insignificant.
Article 402. The Debtor's Responsibility for His Employees
Article 402. The Debtor's Responsibility for His Employees
The actions of the debtor's employees, involved in the discharge of his obligation, shall be regarded as those of the debtor himself. The debtor shall be answerable for these actions, if they have caused the non-discharge or an improper discharge of the obligation.
Article 403. The Debtor's Responsibility for the Actions of the Third Persons
Article 403. The Debtor's Responsibility for the Actions of the Third Persons
Article 403. The Debtor's Responsibility for the Actions of the Third Persons
The debtor shall be answerable for an improper discharge of the obligation by the third persons, on whom the discharge of the obligation has been imposed, unless it has been laid down by the law that the responsibility shall be borne by the third person, who has been an immediate discharger.
Article 404. The Creditor's Guilt
Article 404. The Creditor's Guilt 
1. If the non-discharge or an improper discharge of the obligation has occurred through the fault of both parties, the court shall correspondingly reduce the scope of the debtor's responsibility. The court shall also have the right to reduce the scope of the debtor's responsibility, if the creditor has intentionally or through carelessness contributed to the increase of the losses, caused by the non-discharge or by an improper discharge, or if he has not taken reasonable measures to reduce them.
2. The rules of Item 1 of the present Article shall also be correspondingly applied in the cases, when the debtor, by force of the law or of the contract, bears responsibility for the non-discharge or for an improper discharge of the obligation regardless of whether he is, or is not, at fault.
Article 405. The Debtor's Delay
1. The debtor, who has failed to discharge the obligation on time, shall be answerable to the creditor for the losses, inflicted by the delay, and also for the consequences of the discharge having accidentally become impossible during the period of the delay.
2. If, because of the debtor's delay, the discharge has lost all interest for the creditor, he shall have the right to refuse to accept the discharge and to claim the compensation of the involved losses.
3. The debtor shall not be regarded as guilty of the delay during the period of time, when the obligation could not have been discharged because of the creditor's delay.
Article 406. The Creditor's Delay
1. The creditor shall be regarded as guilty of the delay, if he has refused to accept the proper discharge, offered to him by the debtor, or if he has not performed the actions, stipulated by the law, by the other legal acts, or by the contract, or those stemming from the customs of the business turnover or from the substance of the obligation, before the performance of which the debtor could not have discharged his obligation. The creditor shall also be regarded as guilty of the delay in the cases, pointed out in Item 2 of Article 408 of the present Code. 
2. The creditor's delay shall give to the debtor the right to the compensation of losses, caused to him by the said delay, unless the creditor proves that the delay has occurred through the circumstances, for which neither he himself, nor the persons, to whom, by force of the law, of the other legal acts or of the creditor's commission, the acceptance of the discharge has been entrusted, are answerable.
3. The debtor shall not be obliged to pay the interest by the pecuniary obligation over the period of the creditor's delay.