Under English law, a specialty is a common law category of formal contract valid without consideration. Historically under English law, the usual form of specialty was an instrument under seal. A sealed instrument is one that is signed and has the seal of the signer attached. To render a contract a sealed instrument, it must be so recited in the body of the instrument and a seal must be placed after the signature. Following the enactment of the Law of Property (Miscellaneous Provisions) Act 1989 (an Act of Parliament), it is no longer necessary under English law for a deed to be under seal. Consequently, it is considered that deeds to which the Act applies are specialties even if they are not under seal.
Isle of Man law recognises the concepts of a deed and a specialty. The formalities of Isle of Man deeds differ from those of English deeds in two important aspects. Firstly, there are no stamp duties in the Isle of Man and secondly, the sealing of deeds is unknown in the Isle of Man except (optionally) by corporations/companies.
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