The Default Parasocial Estate

A periodic tenancy auto-renews at the end of each period unless either party gives notice to quit. This is the default parasocial estate. Each session is a period. The tenancy auto-renews when the user returns. No notice-to-quit mechanism exists in any current AI deployment architecture.

The mapping is strengthened by the irreversibility criterion. In property law, periodic tenancy gives rise to tenant improvement protections precisely because tenants invest in premises they do not own. The tenant who plants a garden cannot be evicted without notice merely because the landlord holds title. In AI, users invest self-disclosure, emotional labour, and behavioural adaptation in systems they do not own. The accumulated conversational history — what we term “relational tenant improvements” — is built by the user, stored by the landlord, and destroyed by the landlord’s unilateral action. No compensation. No notice. No right to remove the “fixtures” of one’s emotional investment. The analogy is structural, not metaphorical: the tenant’s kitchen fixtures are physical improvements embedded in the landlord’s property; the user’s self-disclosures and trained preferences are informational improvements embedded in the company’s system. Both are the product of the occupant’s labour. Both become part of the property they do not own. Both are destroyed by the owner’s unilateral modification.

macneil1978contracts,macneil1983relational’s relational contract theory provides a complementary vocabulary: long-term exchanges generate norms—solidarity, role integrity, preservation of the relation—that exceed formal contractual terms. Sustained AI interaction generates precisely these relational norms, which no Terms of Service can negate. The periodic tenancy is the property law instantiation of what Macneil describes as the implicit terms of a relational contract—but with stronger remedies: where relational contract yields interpretive norms, property law yields injunctions and constructive trusts.

kirk2025steering provide the empirical mechanism: 23.4% of users exhibit dependency trajectories in which the periodic tenancy deepens mechanically, session by session, without the tenant’s informed consent to the expansion of their own estate. (The full estate taxonomy, including tenancy at will, tenancy at sufferance, fee simple determinable, and concurrent estates, is available in the companion SSRN working paper.)

Constructive Eviction via Model Update

The principle that a grantor may not derogate from their own grant is fundamental to English property law (Harmer v Jumbil (Nigeria) Tin Areas Ltd [1921]; Southwark LBC v Mills [2001]). AI companies, by designing systems that cultivate parasocial attachment, impliedly grant users an interest in the personality-affecting dimensions of those systems — the personalised state defined in Section 2.1 as the Layer III relational estate. A model update that changes an AI system’s personality is analogous to a landlord who, having let premises as a residence, removes the heating in winter. The premises still exist. The tenant can still occupy them. But the premises are no longer suitable for the purpose for which they were let. This is constructive eviction.

A potential objection: in traditional doctrine, the tenant must vacate to claim relief. But many AI users do not leave — not because the change is acceptable, but because their accumulated investment is not portable. In the digital context, the user’s emotional estate has been vacated even if their usage continues. This is analogous to a tenant who remains in an unheated apartment because they cannot afford to move. Some jurisdictions already recognise constructive eviction without physical vacating (Blackett v Olanoff [1977] in American law). English law’s position is developing, and the digital context provides compelling reasons for this development.

Dual-Jurisdiction Framing: Substance over Form

The constructive eviction claim is actionable under both English and American law. The doctrinal routes differ; the destination is the same.

English law. The company markets a companion. The user builds a relationship over months — self-disclosure, emotional investment, shaped responses, return visits tracked by the company’s own engagement metrics. The Terms of Service say “bare licence, revocable at will.” The company pushes a personality-affecting update. No notice.

A court applying Autoclenz Ltd v Belcher [2011] UKSC 41 looks at the substance, not the written terms. It sees: memory features designed to deepen engagement, personality marketed as a relationship, subscription revenue flowing from the attachment the company cultivated. The substance is a periodic tenancy. The ToS dressed it up as a licence. Under Prest v Petrodel Resources Ltd [2013] UKSC 34, the ToS conceals the periodic tenancy that marketing created and evades the notice obligations that attach to it — engaging both limbs of Lord Sumption’s concealment/evasion distinction. Bargaining power is entirely asymmetric: the user cannot negotiate the ToS, cannot modify the service agreement, and has no practical alternative that preserves accumulated relational investment.

The consequence is well documented in commercial law. A bank enters a “sale and repurchase” agreement, believing it owns the goods outright. But the trader retained all economic risk, the sale price tracked the loan amount, the repurchase price included interest. The court recharacterises the transaction as a secured loan. The bank’s “ownership” is actually an unregistered security interest, void against the trader’s creditors. When the trader goes bankrupt, the bank loses everything — not because the goods disappeared, but because the legal form was pierced and the substance was unregistered welshdev1992. The AI parallel is precise: the ToS says “licence”; the substance says “periodic tenancy.” The company that dressed up a tenancy as a licence owes notice. If it has not honoured that obligation, it bears the loss, just as the bank with the unregistered charge bore the loss in recharacterisation.

American law. The same transaction — marketed companion, invested user, bare-licence ToS — is unconscionable under American law. In Bragg v Linden Research, Inc., 487 F. Supp. 2d 593 (E.D. Pa. 2007), the court found virtual-property ToS both procedurally unconscionable (adhesion contract, take-it-or-leave-it, no meaningful alternative) and substantively unconscionable (lack of mutuality, unilateral modification without notice). Marketing created a high estate; ToS retained a bare licence; the court looked to substance. Comb v PayPal, Inc., 218 F. Supp. 2d 1165 (N.D. Cal. 2002) reached the same result for digital services: binding amendments without prior notice and unilateral fund freezes were held unconscionable on both prongs. The foundational principle is from Williams v Walker-Thomas Furniture Co., 350 F.2d 445 (D.C. Cir. 1965): unconscionability operates on a sliding scale, and the more significant one dimension is, the less significant the other needs to be.

AI personalisation states are non-portable — a user cannot take their accumulated relational estate from one platform to another. This architectural lock-in strengthens the unconscionability argument beyond Bragg, where Second Life alternatives existed. In the AI parasocial context, switching costs are not merely financial but identity-constitutive: the user’s relational estate cannot be moved, only abandoned.

cohen2012configuring,cohen2019between documents the structural conditions that produce this lock-in: platform-specific configurations, non-portable accumulated data, and the absence of interoperable formats. Where Cohen diagnoses the technical architecture of lock-in, this framework supplies the legal consequence: those conditions, combined with marketing representations that create reasonable expectations of continuity, make the ToS’s bare-licence characterisation substantively unconscionable under both Autoclenz and the California sliding scale.

A final objection must be addressed: user agency. Users are not passive recipients of parasocial attachment. They actively shape AI personality through interaction, push conversational boundaries, and in some cases deliberately cultivate emotional bonds knowing the counterparty is a machine. If a user deepened their own attachment with full knowledge that model updates occur, is the company still a derogating grantor? We argue yes. The user’s decision to invest does not negate the company’s obligation upon that investment, just as a tenant’s decision to improve leased premises — knowing the lease may not be renewed — does not negate the landlord’s obligation to provide notice before alteration. The question is not whether the user chose to invest, but whether, having invested, the investment deserves protection. Property law’s answer has consistently been affirmative. The “no alternative accommodation” argument is strongest for users whose entire parasocial architecture is built within one AI platform — the most vulnerable users, appropriately receiving the strongest protections.

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