There is no legal requirement for a company to execute formal contracts and agreements under seal.
If the company is required to have a Seal as spell out by its Articles, Its use must be authorised by the directors. Usually, the Articles provide that affixing of the seal must be witnessed and evidenced by the signature of a director and the company secretary.
Now, the signature of two directors, or a director and the company secretary, signing for and on behalf of the company has the same effect as if the document had been executed under Seal.
You may require a company seal if conducting business abroad or entering into contracts with overseas customers or suppliers, their legal representatives may require that your company affixes an official seal to the commercial contracts.
Many companies still use a Seal to execute official documents in the UK. This is because its use is perceived as a strong authority in signifying a genuine document.
In some countries, a company seal is known as corporate seal or common seal.
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