Think of a company that buys materials every month from the same supplier. The first delivery works with a quotation and an exchange of emails. Later the quantities change and a difference appears: the buyer expected the price to remain in force, while the supplier understood that each order required a new confirmation.
When supply will be recurring, put in writing how each transaction will be accepted. Aim for an agreement that makes it possible to identify what was ordered, what was delivered and what remains to be paid without reconstructing the whole relationship from each department's messages.
Describe the operation before choosing a template
Start by explaining which goods will be supplied and what the buyer will use them for. Identify whether they are catalog goods, parts manufactured to specification or materials subject to change. Also note whether the supplier will reserve capacity or inventory for that account.
Article 78 of the Mexican Commercial Code (Código de Comercio) provides that in commercial agreements each party is bound “in the manner and on the terms in which it appears that it intended to be bound”, without the validity of the act depending on particular formalities or requirements. Article 79 sets out the exceptions to that rule; the first is contracts that under the Code or other laws “must be reduced to a written instrument (escritura) or require forms or solemnities necessary for their effectiveness” [1]. The Code does not devote a chapter of its own to the supply agreement. That is why we recommend that the document describe your operation in detail and that you do not adopt another business's contract without comparing it with yours.
Confirm who the parties will be and who can represent them. If the negotiation includes a subsidiary, a distributor or a company that will only make the payment, ask for its role to be clarified. Check that the name appearing in the business email can be linked to whoever will assume the obligations.
Distinguish the general agreement from each order
Define what will be agreed in the contract itself and what will be completed by a later order. It can be useful to separate the catalog or the specifications from the quantities and dates of each delivery. Identify the attachments and their versions.
Clarify how an order will be sent, who will confirm it and what will happen when it includes different terms. If the supplier needs to accept availability or a date, describe that expressly. Prevent the buyer from reading an acknowledgment of receipt as confirmation of all the terms.
The channels of acceptance deserve attention. Under article 80, commercial agreements and contracts entered into by correspondence, telegraph or through electronic, optical or any other technological means are formed “from the time the acceptance of the proposal, or the conditions with which it was modified, is received” [1]. In the opening example, the difference turned on exactly that: which message counted as acceptance and whether it reached the price of the following orders. Define with your lawyer which communication closes each order, through which channel it is sent and how it is kept.
Identify the goods and the permitted changes
Link each product to its reference, unit of measure and agreed technical documentation. If samples, drawings or certificates are required, state which version will be the reference and who will approve it.
Define what the supplier must do if it proposes a substitution. Ask whether a change in packaging affects your storage or whether a different material requires technical validation. Agree who may authorize those modifications and how the decision will be documented.
Test the clause with an example: the agreed product is not available and another is offered. Reading the contract should make it possible to know whom to consult before shipment and what information that person needs in order to decide.