Jlg Consulting Engineering Psc v. Tetrad Enterprises Limited Liability, KLAN202400046

JLG Consulting Engineering, P.S.C. (JLG) sued Tetrad Enterprises, LLC (TETRAD) for unpaid professional engineering services related to a pump replacement project for the Puerto Rico Department of Natural and Environmental Resources (DRNA).
The contract between DRNA and TETRAD was for over $26 million; JLG designed systems and produced documents for the construction, without receiving payment from TETRAD.
The parties agreed (orally) that JLG would be compensated according to the fee guidelines established by the Colegio de Ingenieros y Agrimensores de Puerto Rico (CIAPR Manual) as a percentage of project cost, applicable to complex works (Category 5).
TETRAD received JLG’s invoices, communicated approval in various ways, but did not pay the claimed amount of $2,354,658.80, calculated pursuant to the CIAPR Manual.
The trial court entered judgment for JLG, finding the debt “liquid, due, and payable,” and TETRAD appealed on several procedural and substantive grounds, primarily contesting the validity and amount of the debt and the process followed by the court.

Issue	Plaintiff's Argument	Defendant's Argument	Held
Whether the debt is liquid, due, and payable	Amount and method of compensation was agreed, calculated per CIAPR Manual, based on cost	No written agreement; debt not liquid/due, requirement for money collection claim not met	Debt is liquid, due, and payable; JLG proved amount and method per agreement
Whether judgment improperly deviated from “law of the case” (prior ruling that debt not liquid)	Later trial evidence established all facts needed; prior ruling was at summary judgment stage	Prior ruling not appealed or changed, so should control (“law of the case”)	No deviation; summary judgment denial just preserved issue for trial, not binding determinatively
Whether lack of written agreement precludes enforceability of contract and fee	Oral agreements are valid and sufficient under PR law; parties admitted to oral deal	No enforceable agreement on terms or amount; perito says no fixed fee	Oral agreement enforceable; sufficient evidence of agreement to CIAPR methodology
Whether the factfinding and judgment resulted from improper summary judgment procedure or lacked evidence	Trial evidence was extensive and uncontradicted; key facts supported by testimony and documents	Trial court just adopted party's facts; relied on “self-serving” statements; ignored defense expert’s views	Trial court’s findings supported by record and due deference owed on credibility

Pueblo v. Hernández Doble, 210 DPR 850 (P.R. 2022) (appellate deference to trial court findings)
Santiago Ortiz v. Real Legacy et al., 206 DPR 194 (P.R. 2021) (trial-level credibility determinations)
Dávila Nieves v. Meléndez Marín, 187 DPR 750 (P.R. 2013) (contract interpretation and enforceability principles)
Méndez v. Morales, 142 DPR 26 (P.R. 1996) (oral contracts are as valid as written under Puerto Rico law)
Vila & Hnos., Inc. v. Owens Ill. de P.R., 117 DPR 825 (P.R. 1986) (enforceability of verbal agreements)