Legal Definitions - in quantum lucratus est

In quantum lucratus est is a Latin legal phrase that translates to "insofar as he has gained or profited." It refers to the extent to which a person has benefited or received a gain, often in situations where a court is determining how much someone should repay or disgorge due to unjust enrichment or a wrongful act. The principle focuses on the actual benefit or profit received by one party at the expense of another.

Here are some examples illustrating this concept:

• Contractor Overbilling: Imagine a homeowner hires a contractor to renovate their kitchen, agreeing to pay for specific high-end materials. The contractor, however, secretly uses cheaper, substandard materials but still charges the homeowner the price for the expensive ones. If the homeowner discovers this deception and sues, a court might apply the principle of in quantum lucratus est to determine the exact amount the contractor gained or profited from using the cheaper materials. The court would order the contractor to repay this specific difference in cost, representing the unjust profit made.

• Unauthorized Use of Intellectual Property: Consider a small clothing company that uses a distinctive design, unknowingly copyrighted by a famous artist, on a line of t-shirts. The t-shirts sell very well, generating significant revenue for the company. When the artist discovers the infringement and sues, the court might use in quantum lucratus est to calculate the profit the clothing company gained specifically from selling the t-shirts with the infringing design. This would involve subtracting the direct costs of producing those specific t-shirts from the revenue they generated, to determine the actual financial benefit derived from the wrongful use.

• Mistaken Payment and Investment: Suppose a bank mistakenly deposits an extra $5,000 into a customer's account. The customer notices the error but decides to keep the money and invests it in a high-performing stock, which quickly doubles their initial $5,000 investment to $10,000. When the bank eventually discovers its error and seeks to recover the funds, a court applying in quantum lucratus est might determine that the customer gained not just the initial $5,000 mistakenly received, but also the additional $5,000 profit from the investment. The court would aim to recover the full extent of the benefit the customer unjustly received and profited from.