Acceptance should be made in accordance with the offer provided by the Master of the Offer. If the offer demands a signature, then acceptance is valid when signed. If acceptance can be done by performance or an action, such as handing a credit card to a cashier, then that is how acceptance is to be made.
The real issue is what happens when the offer does not specify a particular manner of acceptance. The law interprets this as acceptance may be done in any manner which is reasonable.
Reasonable is a great word. It means that so long as both parties understand the actions or manifestation of intent demonstrating acceptance, the offer is accepted and a contract is formed. For example, there is a offer made to the general public for somebody to mow a lawn. If that is the only details, acceptance could be made by giving the owner of the property a phone call to verbally accept the job. Alternatively, someone could show up and mow the lawn, accepting the job by action.
As acceptance is the last step in forming a contract, it is in the best interest of the Master of the Offer to dictate how acceptance is to occur. Look to the example of mowing the yard. One person made a phone call to accept and somebody else mowed the lawn. Now if both occurred the contract could be formed with both individuals and the Master of the Offer would be legally bound to both contracts. This creates problems and can lead to litigation.
Be careful with accepting an offer, as acceptance means there is a legally binding contract between the parties. If the contract is poorly constructed, it can take a lot of time and money to understand the rights and duties of the parties, with enforcement becoming a huge drain of resources.
With the offer accepted, there is a contract. Congratulations, it is time to get to work performing under the contract.
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