Somewhere in your lease there is a sentence you've read three times and decided means what you need it to mean. Maybe it's about who pays for the rooftop unit, or whether a renewal rent is "fair market" or "prevailing," or what counts as a "substantial" alteration. You've told yourself the landlord's lawyer wrote it, so if it's fuzzy, the fuzz must cut your way. It's a comforting thought. It's also, in a commercial setting, one of the most expensive assumptions a tenant can carry into a dispute.

The story you tell yourself about vague wording

There is a real legal doctrine behind the comfort. It's called contra proferentem: when a contract term is truly ambiguous, it may be read against the party who drafted it. Tenants hear this once, usually from a friend, and it hardens into a rule of thumb: if it's unclear, it's the landlord's problem.

But the doctrine is narrower than the folk version. In many jurisdictions courts treat it as a last resort, reached only after every other tool for finding the parties' meaning has failed. And between two commercial parties, who are presumed to have had the chance to negotiate and to hire lawyers, courts are often less willing to lean on it at all. A consumer signing a form with no leverage gets more sympathy than a business owner who could have asked for changes.

The details vary by state, so none of this is a prediction about your lease. The point is structural: "unclear" is not a verdict. It's the beginning of a much longer and more expensive process.

What a court actually does with an unclear clause

Think of interpretation as a series of gates, and the doctrine that favors you sits near the end.

First, the court asks whether the language is ambiguous at all. Many courts start with the plain meaning of the words, read within the four corners of the document. A clause you find baffling may still be judged clear, because a judge can often find a reasonable single reading when you can't. Ambiguity is a legal conclusion, not a feeling.

Second, the court reads the whole lease. A phrase that looks open-ended in isolation may be pinned down by a definition three pages earlier or an exhibit at the back. Courts generally try to give effect to every provision and avoid readings that make another clause pointless.

Third, the court applies the ordinary canons. Specific language commonly controls over general language. Negotiated, typed or handwritten additions commonly control over pre-printed boilerplate. Defined terms mean what the definition says, even when everyday usage points elsewhere.

Fourth, if genuine ambiguity survives, outside evidence may come in. Emails during negotiation, drafts, how the parties behaved for years. Once that door opens, the question often becomes one of fact rather than law, which can push a case away from early dismissal and toward discovery and trial. That's slower, costlier, and less predictable.

Only then, in many places, does the tiebreaker against the drafter come into play. Fifth gate of five. Plenty of disputes never reach it, and plenty of tenants spend their budget getting there only to be told it doesn't apply to sophisticated parties.

Why we are bad judges of our own lease

Here's the quieter problem. You are not a neutral reader of your own contract.

Behavioral research on negotiation and dispute resolution describes a self-serving bias in fairness judgments: people exposed to the same facts tend to read them in the way that favors their side, and they sincerely believe their reading is the objective one. Linda Babcock and George Loewenstein's well-known work on bargaining impasses is the classic reference. Their finding, in short, is that this bias makes settlement harder, because each side thinks the neutral outcome happens to be the one that favors them.

Apply that to an ambiguous clause. When you read "Tenant shall maintain the premises in good order," you hear the cosmetic sense, paint and cleanliness. The landlord reads the same line and hears the structural sense, including the roof and the HVAC. Neither of you is lying. Each of you resolved the ambiguity silently, in your own favor, the first time you read it, and has been reinforcing that reading ever since.

The damage isn't just legal. It's that you stop looking. A clause you've already decided is on your side never gets a second read, never gets a clarifying email, and never gets fixed while fixing it is cheap.

The cheapest moment to resolve ambiguity is before it matters

Ambiguity costs almost nothing to remove at signing and a great deal to litigate afterward. A question that takes a one-line amendment today can take months and five figures in legal fees once money is riding on the answer.

And there's a trap in the other direction. Many leases contain an entire agreement clause that says the written document replaces earlier conversations. If a broker or property manager once told you what a vague phrase "really means," that comfort may not be admissible, or may carry no weight, when the dispute arrives. The memory in your head is not evidence the clause will respect.

The same goes for later conduct. A landlord's silence, or a verbal "don't worry about it," generally doesn't amend a written lease, and non-waiver provisions often say so directly. What you want is clarification in a form the lease itself recognizes: a signed writing.

Your next moves

  • Find your three most-argued clauses today. Open the lease and mark every sentence that decides who pays for something: repairs, replacements, renewal pricing, restoration, expense pass-throughs. Those are where ambiguity is expensive.
  • Write each one in plain English, then try to argue the other side. Take ten minutes per clause and draft the landlord's strongest reading. If you can build a credible one, the clause is genuinely contestable and you should not assume you'd win.
  • Check the definitions and exhibits. Search the lease for each capitalized term in those clauses and read its definition. Many apparent ambiguities collapse, for better or worse, once you see how the lease defines its own words.
  • Send a clarifying email, then ask for a signed amendment. An email stating "our understanding is that X means Y, please confirm" creates a record and surfaces disagreement while it's still cheap. If the landlord confirms, ask that it be memorialized in a signed amendment or side letter that follows the lease's own notice and amendment rules. A reply email alone may not satisfy those rules.
  • Book one hour with a commercial real estate attorney for the highest-dollar clause. Interpretation rules differ by state, and a local lawyer can tell you whether your jurisdiction would reach the drafter-tiebreaker at all. This is general information, not legal advice for your lease.

Where this leaves the tenant who tracks things

What the five gates really reward is paperwork: definitions understood, clarifications sent, amendments signed, dates tracked. The tenant who wins an interpretation fight is rarely the one with the sympathetic reading. It's the one who noticed the soft spot early and had the answer written down before anyone had a reason to disagree.

That's the part of lease management that fades first, because it lives in a PDF no one reopens until there's a problem. Closeout is built around keeping a lease's obligations, deadlines, and the loose ends you promised yourself you'd clarify in view, so the unclear clause gets a second look while a second look is still cheap. If that sounds useful, you can see how it works at https://closeout.lumenlabs.works.