A civil-law concept defining a rule, doctrine, or procedural mechanism used to resolve private disputes. It applies when its legally specified conditions are satisfied and produces defined consequences in adjudication or settlement. It does not apply where required elements or prerequisites are not met. It materially affects rights, obligations, or available remedies in civil controversies. The concept is generally stable, though statutory and doctrinal refinements may occur over time.

Principle

Past interactions between the same parties can create expectations about contract terms and performance standards, so a judge may interpret ambiguous provisions in light of that established pattern of dealing.

Demonstration

A buyer and supplier have transacted for years where the supplier routinely shipped goods FOB and the buyer assumed risk accordingly. A later dispute over a similar clause will be interpreted in light of that historical course of dealing.

Misapplication

Relying on prior dealings with different parties, or isolated past interactions, to fix the meaning of terms in a new contract between different parties misapplies the doctrine.

Consequence

Proper use of course of dealing promotes interpretive consistency across related transactions and can demonstrate implied terms, trade habits between the parties, or tacit modifications carried forward into new agreements.

Reversal

The reversal treats each contract in isolation: historical interactions are ignored, so identical terms may be read differently absent evidence of a shared past practice, increasing unpredictability in ongoing commercial relations.

Boundary

Concerned with past transactions between the same parties (not industry practice); requires a pattern sufficient to establish mutual expectations and does not override clear, unambiguous contract language unless the past dealings show an unmistakable contrary intent.

Semantic Tension

Closely related to trade usage and course of performance: trade usage captures industry norms, course of dealing captures bilateral history, and course of performance captures conduct under the current contract; courts must prioritize the most specific context.

Synthesis

Course of dealing is the demonstrable history of transactions between parties that supplies factual context for interpreting subsequent agreements, helping courts infer mutual expectations and implied contractual terms.