Acceptance under the CISG
An acceptance may be a statement or conduct indicating assent. Silence or inactivity alone is not acceptance. Normally it becomes effective when the indication reaches the offeror within the applicable time. Where the offer, practices or usage permits assent by performing an act without notice, acceptance can instead be effective when that act is performed in time. CISG article 19 treats material changes differently from non-material additions that are not promptly objected to.
Worked example
A seller offers 100 units at $10 each; the buyer sends unconditional assent which reaches the seller before the deadline. If the reply changes the price to $9, it is normally a rejection and counter-offer.
Common mistake
Applying the English postal rule automatically, or assuming every additional term necessarily prevents acceptance.
Where it appears in your exams
| Qualification | Exam | Relationship | Period |
|---|---|---|---|
| ACCA | LW (GLO) | Direct | September 2026–June 2027 |