Mention the document of which registration is optional.

Section 18 of the Registration Act, 1908 lists the documents whose registration is left to the choice of the parties rather than compelled by law — these fall into six categories, each corresponding to a lower-value or otherwise less consequential counterpart of the compulsorily registrable documents under Section 17.

Documents of Optional Registration — Section 18

Clause (a) covers instruments, other than instruments of gift and wills, which purport or operate to create, declare, assign, limit or extinguish, whether in present or in future, any right, title or interest, whether vested or contingent, to or in immovable property, where the value of such right is less than one hundred rupees. This is the low-value mirror image of Section 17(1)(b) — the same class of transaction falling below the value threshold that makes registration compulsory. Instruments of gift are excluded from this optional category because, regardless of value, they are separately made compulsorily registrable under Section 17(1)(a); wills are excluded because they are governed by their own distinct regime.

Clause (b) covers instruments acknowledging the receipt or payment of any consideration on account of the creation, declaration, assignment, limitation or extinction of such a right, again where the value is below Rs 100 — the optional counterpart to Section 17(1)(c).

Clause (c) covers leases of immovable property for any term not exceeding one year, and leases exempted from compulsory registration under the proviso to Section 17(1) — that is, leases with a term not exceeding five years and an annual rent not exceeding fifty rupees, where the State Government has issued the relevant notification.

Clause (cc), inserted by the 1929 amendment, covers instruments transferring or assigning a decree, order of court, or arbitral award, where the decree, order or award itself purports to create, declare, assign, limit or extinguish a right of a value less than one hundred rupees in immovable property — the low-value counterpart to Section 17(1)(e).

Clause (d) covers instruments, other than wills, which purport or operate to create, declare, assign, limit or extinguish any right, title or interest to or in movable property. Since Section 17 governs only immovable property, any document dealing exclusively with movable property remains, at most, optionally registrable, irrespective of its value.

Clause (e) covers wills. A testator may present his will for registration during his lifetime, though he is under no obligation to do so, and the will's validity as a testamentary instrument is unaffected by registration or its absence.

Clause (f) is the residuary category, sweeping in all other documents not required by Section 17 to be registered.

Illustrations

A sale deed conveying a small plot of land valued at Rs 80 falls under clause (a) and may, but need not, be registered, since its value is below the Rs 100 threshold in Section 17(1)(b). A short lease of a shop for eight months, or an eleven-month tenancy agreement renewable by mutual consent, falls under clause (c), leaving registration entirely to the discretion of the landlord and tenant. A hire-purchase agreement or a deed of gift relating to a motor vehicle or jewellery — being movable property — falls under clause (d) and may be voluntarily registered, though this is rarely done in practice. A person executing a will bequeathing his estate to his children may choose to register it during his lifetime under clause (e), a step often taken as a precaution against later allegations of tampering, forgery, or loss of the original, though the will remains fully valid, and equally revocable, whether registered or not.

Judicial Treatment

Courts have repeatedly clarified the boundary between the compulsory and optional categories by scrutinising the substance, not merely the form, of the document in question. In determining whether an instrument falls under Section 17(1)(b) or its optional counterpart in Section 18(a), the value of the right created or extinguished is the decisive factor, and where that value is genuinely below Rs 100 — a threshold that, admittedly, renders clause (a) of little practical relevance today given inflation in property values — registration cannot be insisted upon as a matter of law, and a document within this class remains fully valid and admissible in evidence even though unregistered, since Section 49's bar on unregistered documents applies only to documents "required" to be registered under Section 17, not to those merely permitted to be registered under Section 18.

This distinction was significant in cases concerning wills bearing recitals of gift or family arrangements. In Mathai Samul v. Eapen Eapen, the Supreme Court examined a composite document containing recitals that partly resembled a family arrangement, partly a gift, and partly a testamentary bequest, and undertook the exercise of separating which of these recitals could be given legal effect even without registration — recognising that testamentary dispositions within such a document, being will-like in character, did not require registration to take effect, consistent with the optional status accorded to wills under Section 18(e).

The optional character of wills has also been considered alongside the broader debate on whether registration should be made compulsory for testamentary instruments to reduce disputes over authenticity — a reform that has been discussed in academic and judicial commentary but has not, so far, been enacted, leaving Section 18(e) as the governing rule: a will remains valid and enforceable through probate proceedings whether or not it has been registered, and registration serves only an evidentiary, precautionary function.

On leases falling under clause (c), courts have consistently held that a lease for a term not exceeding one year, even where it involves valuable property, remains outside the compulsory net of Section 17(1)(d) and may be created and proved without any registered instrument at all, oral evidence or an unregistered writing being equally admissible to establish its terms — a position frequently invoked in landlord-tenant disputes involving short-term leave-and-licence arrangements or annual tenancies just short of the one-year threshold.

Documents relating to movable property under clause (d) have rarely generated significant litigation on the question of registration itself, since movable property transactions are more commonly governed by considerations of delivery of possession and documentary proof under the Sale of Goods Act and the Indian Evidence Act rather than by the Registration Act; nevertheless, courts have affirmed that nothing in law prevents parties from registering such instruments if they wish to create a more durable and easily provable public record of the transaction.

Comparative Summary