Historical Context & Motivation
The distinction between assignment and sublease has roots deep in the English common law of estates, where the concept of privity of estate governed who owed obligations to whom. Medieval landlord-tenant law was structured around feudal tenure, and courts needed a principled way to determine whether a tenant's transfer of possession to a third party created a direct legal relationship between that third party and the original landlord. The answer depended on the nature of the transfer—whether the tenant parted with everything or retained a reversionary interest. This doctrinal framework has survived, with modifications, into modern American property law and remains a staple of bar examination testing.
The fundamental question this doctrine addresses is deceptively simple: when a tenant (T) transfers possessory rights to a third party (T2), does T2 step into T's shoes and assume a direct relationship with the landlord (L), or does T remain as an intermediary? The answer determines who can sue whom for breach of lease covenants, who owes rent to the landlord, and what remedies are available—all of which are heavily tested on the Multistate Bar Examination.
Core Principles & Definitions
The distinction between assignment and sublease turns on a single, deceptively elegant principle: how much of the leasehold term does the original tenant transfer? Under the traditional common law rule, if the tenant transfers the entire remaining term of the lease to a third party, the transfer is an assignment. If the tenant retains any part of the remaining term—even a single day—the transfer is a sublease. This rule applies regardless of what the parties call the transaction; substance controls over labels.
Assignment
Sublease
Privity of Estate
Privity of Contract
Reversionary Interest
Visual Explanation — Assignment vs. Sublease
The diagram above illustrates the fundamental structural difference between the two transfers. In the assignment scenario, notice how the green curved arrow shows the creation of new privity of estate between L and T2—this is the hallmark consequence of assignment. The landlord gains the ability to enforce covenants that touch and concern the land directly against the assignee. In the sublease scenario, notice the absence of any direct connection between L and T2. The subtenant's only legal obligations flow upward to T1, while T1 remains the party directly accountable to the landlord for all lease obligations. This structural distinction is what makes the classification so consequential for questions of covenant enforcement and liability.
How It Works — The Traditional Rule & Its Alternatives
The Traditional (Majority) Rule
Under the traditional common law rule—and the rule tested on the MBE—the classification of a transfer as an assignment or sublease depends solely on whether the transferor has retained a reversionary interest. The inquiry is mechanical and objective: compare the duration of the transfer to the remaining duration of the original lease. If the transfer covers the entire remaining term, it is an assignment. If the transfer covers anything less than the entire remaining term—whether by one day or several years—it is a sublease. Importantly, the parties' intent, the label they use in their agreement, and the inclusion of rent obligations to the landlord are all irrelevant under this approach.
The Minority (Intent-Based) Rule
A minority of jurisdictions, influenced by the Restatement (Second) of Property (Landlord and Tenant), adopt an intent-based approach. Under this view, courts look to the actual intent of the parties—as evidenced by the language of the transfer agreement, the inclusion of assumption clauses, whether rent is payable to the landlord or to the original tenant, and other surrounding circumstances—to determine whether the transfer was meant to be an assignment or a sublease. While this approach may yield more equitable results in specific cases, it introduces uncertainty and is not the default rule on the bar exam.
Consequences of Classification
- Covenant enforcement: In an assignment, the landlord can enforce covenants that touch and concern the land against T2 through privity of estate. In a sublease, the landlord cannot directly enforce any covenant against T2.
- Rent liability: An assignee in privity of estate with L is directly liable to L for rent (a covenant that touches and concerns the land). A subtenant owes rent only to T1, not to L.
- T1's continuing liability: Regardless of whether the transfer is an assignment or sublease, T1 remains liable to L under privity of contract for the full lease term, unless L agrees to a novation (releasing T1).
- Landlord's remedies: In an assignment, the landlord can pursue either T1 (contract) or T2 (estate) for unpaid rent. In a sublease, the landlord's only recourse is against T1.
Privity Analysis — Mapping Legal Relationships
Understanding the distinction between assignment and sublease requires mastery of two overlapping but distinct doctrines: privity of estate and privity of contract. These concepts determine who can sue whom and for what. The following table maps these relationships across all possible transfer scenarios, which is essential for answering bar exam questions that present chains of assignments, subleases, or both.
| Transfer Type | L–T1 Privity of Estate | L–T1 Privity of Contract | L–T2 Privity of Estate | L–T2 Privity of Contract |
|---|---|---|---|---|
| Assignment | Destroyed | Survives | Created | None (unless assumed) |
| Sublease | Survives | Survives | None | None |
Worked Example — Classifying a Transfer
Consider the following fact pattern, which is representative of the kind of question you will encounter on the bar exam. Pay close attention to the dates and the precise language of the transfer.
Assignment vs. Sublease — Comprehensive Comparison
| Feature | Assignment | Sublease |
|---|---|---|
| Term transferred | Entire remaining term | Less than the entire remaining term |
| Reversionary interest | None retained by T1 | Retained by T1 |
| L–T2 privity of estate | Yes | No |
| L can sue T2 for rent | Yes (touch & concern covenant) | No (absent third-party beneficiary theory) |
| T1's continuing liability to L | Yes (privity of contract) | Yes (privity of contract and estate) |
| T2's landlord | L (directly) | T1 (as sublandlord) |
| Labels matter? | No (substance over form) | No (substance over form) |
| Effect on anti-assignment clause | May violate restriction on assignment | Does not violate restriction on assignment (and vice versa) |
Advanced Issues — Successive Transfers, Novation, & Assumption
Bar exam questions frequently test not just the basic assignment-sublease distinction but also its intersection with the doctrines of novation, assumption, and successive transfers. Understanding how these concepts interact is essential for navigating complex multi-party scenarios.
| Concept | Definition | Effect on Privity |
|---|---|---|
| Novation | A three-party agreement in which the landlord releases T1 from all obligations and accepts T2 as the new tenant. | Destroys L–T1 privity of contract. T1 is no longer liable. Only way to release T1 from contractual liability. |
| Assumption | An assignee's express agreement (typically in the assignment document) to perform all obligations under the original lease. | Creates privity of contract between L and T2 (as third-party beneficiary). T1 remains liable unless novation occurs. |
| Re-assignment by T2 | T2 assigns the entire remaining term to T3. T2 is no longer in privity of estate with L. | L–T2 privity of estate is destroyed. L–T3 privity of estate is created. L–T1 privity of contract persists. If T2 assumed, T2 remains in privity of contract with L. |
| Restriction clauses | Lease provisions prohibiting assignment, sublease, or both. Courts strictly construe these restrictions. | A restriction on 'assignment' does not bar subleasing, and vice versa. Waiver by the landlord of one breach does not waive future breaches. |
One particularly important advanced issue concerns the liability of an assignee who subsequently re-assigns. When T2 (an assignee) transfers the entire remaining term to T3, T2's privity of estate with L is terminated—and with it, T2's liability for covenants running with the land going forward. However, if T2 expressly assumed the obligations of the original lease, T2 remains liable to L under privity of contract even after re-assigning. This distinction between liability based on privity of estate (which travels with the leasehold) and liability based on privity of contract (which is personal and enduring) is a frequent source of bar exam questions.
Practice Problems
Summary — Assignment & Sublease Distinguished
The distinction between assignment and sublease turns on a single question under the traditional common law rule: did the original tenant transfer the entire remaining term? If yes, the transfer is an assignment and privity of estate shifts from L–T1 to L–T2, enabling the landlord to enforce covenants that touch and concern the land directly against the assignee. If the tenant retains any reversionary interest—even a single day—the transfer is a sublease and the landlord has no direct relationship with the subtenant.
Regardless of whether the transfer is classified as an assignment or sublease, T1 remains liable to L under privity of contract unless released by novation. An assignee who expressly assumes the lease obligations creates privity of contract with L that persists even after re-assignment. Labels do not control; substance governs over form. Finally, lease restrictions on assignment and sublease are strictly construed—a clause barring one does not bar the other.