In this case, the tender arrived on time, but lay in the letterbox, therefore it was deemed to be a valid offer.
A unilateral contract would turn into a bilateral contract through a valid acceptance, signified by a performance of the stipulated terms within the offer. According to I.M. Wormser, the justification for fixing acceptance to a unilateral contract upon completed performance of the stipulated terms is based upon symmetry3. Therefore in terms of the tender, there is no obligation upon the offerer, neither is there any obligation upon the offeree unless and until the stipulated terms of the offer have been completed. An offeree need not perform the stipulated terms, in which case no contract exists. Therefore, the initial tender was sent to Widget by Dig-it Builders but when accepted by Widget, did not yet constitute a formal contract because Dig-it sent a counter offer and when it was not accepted within the stipulated time period, they sent the fax withdrawing their offer. However the original term of the tender is 60 days so the tender still remains open, since only one party has withdrawn the offer. The mail indicating acceptance by Widget was posted by the architect on the same day, and the courts have deemed acceptance when a letter is posted4. However it is received on the subsequent day (the 35th) day of the tender. Therefore, this will still be subject to the general rule regarding acceptance, which is the requirement of actual communication5. No legal commitment will be deemed to exist until the acceptance of the offer is communicated to the offerer and up to that point, either party is free to change their minds.6 However, Dig-it’s fax will be construed to be a counter offer in the sense that it is a withdrawal of the original offer, which no longer exists. But the tender is not yet closed because Dig-it has made a counter offer reducing the price, although this will still not be a contract until acceptance is obtained