Obligations are one of the foundational subjects in Philippine civil law. They govern the juridical necessity to give, to do, or not to do. In the Philippines, the law on obligations is principally found in the Civil Code, especially in Book IV, Title I. A proper understanding of the classifications of obligations is essential because the classification determines the rights of creditors, the duties of debtors, the remedies available in case of breach, the effect of loss or impossibility, the rules on delay, and the consequences of fraud, negligence, or fortuitous events.

This article presents a full discussion of the classifications of obligations in Philippine civil law, organized by their legal nature, object, parties, demandability, and sanctions.

I. Nature and Concept of Obligation

An obligation is a juridical necessity to give, to do, or not to do.

From this definition, the essential elements of an obligation are:

1. Active subject The person who has the right to demand performance. This is the creditor or obligee.

2. Passive subject The person bound to perform the prestation. This is the debtor or obligor.

3. Prestation The conduct required: to give, to do, or not to do.

4. Juridical or legal tie The vinculum juris, or legal bond, which makes the obligation enforceable.

The law on obligations classifies obligations in several ways because not all obligations operate in the same manner. A debt payable immediately is not the same as one subject to a suspensive condition; a debt with several debtors is not the same as a solidary debt; an obligation to deliver a determinate thing is not governed exactly like one to deliver a generic thing.

II. Primary Classification According to Prestation

A. Obligation to Give

This is an obligation whose object is the delivery of a thing.

It may involve:

1. A determinate or specific thing A determinate thing is one particularly designated or physically segregated from others of the same class.

Example: “To deliver the specific car with plate number ABC 123.”

2. A generic or indeterminate thing A generic thing is identified only by its class or genus.

Example: “To deliver one sack of rice.” “To deliver a Toyota sedan.”

Legal consequences of an obligation to give

Where the obligation is to deliver a determinate thing, the creditor may compel specific performance. The debtor must preserve the thing with the diligence required by law, stipulation, or the nature of the obligation. The creditor also has rights to the fruits from the time the obligation to deliver arises, although real rights over the thing itself are acquired only upon delivery.

Where the obligation is to deliver a generic thing, the rule is that the debtor cannot excuse nonperformance by claiming loss of the thing, because genus never perishes. The creditor may ask that the obligation be performed at the debtor’s expense.

Accessories and accessions

When one is bound to deliver a determinate thing, the obligation includes delivery of its accessions and accessories, even if not mentioned, unless a contrary intention appears.

B. Obligation to Do

This refers to an obligation to render service or perform an act.

Examples:

To construct a house
To paint a portrait
To transport goods
To provide legal or medical services

If the debtor fails to do what he is obliged to do, the same may be executed at his cost. If the act was done in contravention of the tenor of the obligation, it may be ordered undone, if possible.

Some obligations to do involve personal qualifications or special skill. In such cases, courts are generally cautious in compelling literal performance if it amounts to involuntary servitude or requires highly personal acts. Damages often become the practical remedy.

C. Obligation Not to Do

This is an obligation to refrain from an act.

Examples:

Not to build beyond a height restriction
Not to open a competing business within a certain area, if validly stipulated
Not to disclose confidential information

If the obligor does what has been forbidden, it shall be undone at his expense, where possible, without prejudice to damages.

III. Classification According to Civil Code Demandability and Effect

This is one of the most important groupings in the Civil Code.

A. Pure Obligations

A pure obligation is one not subject to any condition and without a specific term, or one already demandable at once.

It is immediately demandable.

Example: “I promise to pay ₱100,000.” If no condition and no period qualify the debt, it can generally be demanded at once.

Effect

The creditor may immediately enforce it upon maturity of the juridical relation, without waiting for any future event.

B. Conditional Obligations

A conditional obligation is one whose effectivity or extinguishment depends upon a future and uncertain event, or upon a past event unknown to the parties.

Conditions are crucial because they affect either:

the birth or demandability of the obligation, or
the extinguishment of an already existing obligation.

1. Suspensive Condition

A suspensive condition suspends the demandability or effectivity of the obligation until the condition happens.

Example: “I will give you ₱50,000 if you pass the Bar.”

Before the condition is fulfilled, the obligation is not yet demandable. Upon fulfillment, the obligation becomes effective.

2. Resolutory Condition

A resolutory condition extinguishes an obligation already existing once the condition occurs.

Example: “I will allow you to use the land until the owner returns from abroad.”

The obligation or right exists now, but it is subject to termination upon the happening of the condition.

IV. Specific Rules on Conditions

A. Casual, Potestative, and Mixed Conditions

1. Casual Condition

A condition whose fulfillment depends on chance or on the will of a third person.

Example: “If the ship arrives safely.” “If X approves the project.”

2. Potestative Condition

A condition dependent upon the will of one of the parties.

This requires careful distinction:

If the condition is suspensive and depends solely on the will of the debtor, the obligation is void.
If it depends solely on the creditor’s will, or if it is resolutory, different consequences may apply.

Example of void condition: “I will pay you if I want to.” This is void because the debtor can defeat the obligation at pleasure.

3. Mixed Condition

A condition partly dependent on the will of one of the parties and partly on chance or the will of a third person.

Example: “I will sell you the house if you obtain bank financing.” The buyer must act, but bank approval depends on a third person.

B. Impossible, Illegal, and Immoral Conditions

Conditions that are:

impossible,
contrary to law,
contrary to morals,
contrary to good customs,
contrary to public order, or
contrary to public policy

may invalidate the obligation or be deemed not imposed, depending on the character of the obligation and the condition.

In obligations to give

If the condition is impossible or unlawful, the obligation dependent upon it is generally void.

In obligations not to do

Impossible conditions are generally disregarded.

Example: “I will give you my car if you touch the moon with your hand.” The suspensive condition is impossible, so the obligation is void.

C. Positive and Negative Conditions

1. Positive Condition

Requires that an event happen at a determinate time.

Example: “I will pay you if your vessel arrives before June 30.”

If the time expires or it becomes indubitable that the event cannot happen, the obligation is extinguished or does not arise.

2. Negative Condition

Requires that an event does not happen at a determinate time.

Example: “I will pay you if no lawsuit is filed against the property before December 31.”

If the time expires without the event taking place, the obligation becomes effective.

D. Divisible and Indivisible Conditions

A condition may be physically or juridically divisible or indivisible, depending on whether it can be partially fulfilled.

This distinction matters in reciprocal obligations and in determining substantial compliance, though the Civil Code’s more formal treatment of divisibility is usually discussed under prestations rather than conditions.

E. Constructive Fulfillment of Suspensive Condition

If the obligor voluntarily prevents the fulfillment of the suspensive condition, the condition is deemed fulfilled.

Example: A seller promises to convey land if the buyer secures a permit, but the seller later blocks the application through bad faith interference. The law treats the condition as fulfilled.

This rule prevents a party from profiting from his own wrongful conduct.

F. Rights Pending Fulfillment of Condition

Before the suspensive condition is fulfilled:

the creditor has a mere expectancy or inchoate right;
the debtor may recover what was paid by mistake while the condition was pending if payment was not yet due.

When the condition is resolutory:

rights already acquired are subject to loss upon happening of the condition.

G. Loss, Deterioration, or Improvement Pending Condition

In obligations to deliver a determinate thing subject to a suspensive condition, if the thing is lost, deteriorates, or improves while the condition is pending, the Civil Code provides detailed rules:

If the thing is lost without the debtor’s fault: the obligation is extinguished. If lost through debtor’s fault: debtor pays damages. If it deteriorates without debtor’s fault: impairment is borne by the creditor. If it deteriorates through debtor’s fault: creditor may choose rescission or fulfillment, with damages in either case. If it improves by nature or time: benefit goes to creditor. If improved at debtor’s expense: debtor has rights similar to a usufructuary.

These rules reflect equitable allocation of risk during the pendency of the condition.

V. Obligations with a Period or Term

An obligation with a period is one whose demandability or extinguishment depends upon a future and certain event.

Unlike a condition, the event is certain to happen, though the exact time may be unknown.

Example: “I will pay you on December 31.” “I will pay you when my father dies.” Death is certain, though the exact date is unknown.

A. Suspensive Period (Ex Die)

The obligation becomes demandable only upon arrival of the day certain.

Before arrival of the period, the debt exists but is not yet demandable.

B. Resolutory Period (In Diem)

The obligation is demandable now, but it terminates upon arrival of the day certain.

Example: “A lease for one year ending on June 30.”

C. Benefit of the Period

As a rule, a period is presumed established for the benefit of both creditor and debtor, unless the contrary appears from:

the stipulation,
the circumstances, or
the nature of the obligation.

If for the debtor’s benefit alone, he may perform before the arrival of the term. If for the creditor’s benefit alone, he may demand performance before the term.

D. When Debtor Loses the Right to Use the Period

The debtor may lose the benefit of the period in certain cases, such as when he:

becomes insolvent after the obligation is contracted, unless he gives guaranties or securities;
does not furnish promised guaranties or securities;
impairs those guaranties by his acts;
when through fortuitous event they disappear, unless immediately replaced;
violates any undertaking in consideration of which the creditor agreed to the period;
attempts to abscond.

In these cases, the obligation becomes immediately demandable.

E. Court Fixing the Period

When no period is specified but from the nature and circumstances it can be inferred that one was intended, the court may fix the duration.

The court may also fix the period if the period depends solely upon the will of the debtor.

Example: “I will pay you when my finances permit.” This is not necessarily void, but the court may fix a period.

VI. Alternative and Facultative Obligations

These are classifications based on the object or prestations due.

A. Alternative Obligations

An alternative obligation is one where several prestations are due, but performance of one is sufficient.

Example: “I will deliver either my laptop, my printer, or ₱30,000.”

Right of Choice

As a rule, the debtor has the right of choice unless expressly granted to the creditor.

The choice produces no effect except from the time it has been communicated.

Limits on Choice

The debtor cannot choose prestations that are:

impossible,
unlawful, or
could not have been the object of the obligation.

Loss of Objects in Alternative Obligations

The effects depend on:

who has the right of choice,
whether the loss is due to fortuitous event or fault,
whether all or only some prestations are lost.

If the debtor has the right of choice and one prestation is lost by fortuitous event, he may choose among the remainder. If all are lost through fortuitous event before delay, the obligation is extinguished. If all are lost through his fault, liability attaches according to Civil Code rules.

If the creditor has the right of choice, the debtor’s fault in causing loss of one or more objects may increase the creditor’s remedies.

B. Facultative Obligations

A facultative obligation is one where only one prestation is due, but the debtor may substitute it with another.

Example: “I will deliver my specific watch, but I may give my ring instead.”

The key difference from an alternative obligation is this:

In an alternative obligation, several prestations are due, but one suffices.
In a facultative obligation, only one prestation is due; the substitute is merely permitted.

Effect of Loss

Before substitution is made, loss of the substitute does not affect the obligation, because it is not the principal object. After substitution has been validly made, the substitute becomes the due prestation.

VII. Joint and Solidary Obligations

This classification concerns the number of subjects.

A. Joint Obligations

A joint obligation exists when there are several creditors, several debtors, or both, and the liability or credit is divided among them.

There is no presumption of solidarity. The presumption is jointness, unless solidarity is:

expressly stated,
required by law, or
required by the nature of the obligation.

Example: A, B, and C owe X ₱90,000 jointly. Each debtor is liable only for ₱30,000.

Likewise, if X, Y, and Z are joint creditors, each may demand only his proportionate share.

Characteristics

Each debtor answers only for his own part.
Insolvency of one debtor is not borne by the others unless stipulated.
A joint creditor cannot demand the whole.

B. Solidary Obligations

A solidary obligation exists when each debtor may be compelled to pay the entire obligation, or each creditor may demand the whole performance.

Solidarity must not be lightly presumed.

Types of solidarity

1. Active solidarity Several creditors, each entitled to demand the whole.

2. Passive solidarity Several debtors, each liable for the whole.

3. Mixed solidarity Several creditors and several debtors.

C. Effects of Passive Solidarity

Where debtors are solidarily liable:

the creditor may proceed against any one of them, some of them, or all of them simultaneously;
demand against one does not bar proceeding against others while the debt remains unpaid;
payment by one extinguishes the obligation;
the paying debtor may recover from co-debtors only their corresponding shares, with interest if appropriate.

Defenses available to a solidary debtor

A solidary debtor may raise:

defenses derived from the nature of the obligation;
defenses personal to him;
defenses personal to other co-debtors, but only as to their share.

Insolvency of a co-debtor

If one solidary debtor pays and another is insolvent, the loss is borne by all co-debtors proportionately, including the payer, subject to the debtor’s own share.

D. Effects of Active Solidarity

Any solidary creditor may demand the whole obligation, but payment made to one of them extinguishes the obligation.

A debtor may pay any one of the solidary creditors, unless judicial demand has been made by one, in which case payment should be made to that creditor.

A solidary creditor who collects the debt must account to the others for their shares.

E. Solidarity Distinguished from Indivisibility

These concepts are often confused.

Solidarity refers to the legal tie among parties.
Indivisibility refers to the prestation.

A debt may be:

solidary and divisible,
solidary and indivisible,
joint and divisible,
joint and indivisible.

Example: Three debtors bound jointly to deliver one specific horse: the obligation is joint as to parties but indivisible as to object.

VIII. Divisible and Indivisible Obligations

This classification is based on whether the prestation can be partially performed.

A. Divisible Obligations

Those susceptible of partial performance.

Examples:

Payment of money in installments, if allowed
Delivery of fungible goods by portions
Performance of acts measurable in parts

B. Indivisible Obligations

Those not susceptible of partial performance, either by nature, by stipulation, or by law.

Examples:

Delivery of a specific car
Execution of a particular deed
Construction of a house according to one integrated plan, depending on terms

Tests of indivisibility

Indivisibility may arise from:

the nature of the thing;
the intention of the parties;
legal provisions.

A thing physically divisible may still be juridically indivisible if the parties so agree.

Example: A debt of ₱1,000,000 payable only in one lump sum can be treated as indivisible by stipulation.

C. Effects Where Obligation Is Joint and Indivisible

If several debtors are jointly bound in an indivisible obligation, the obligation cannot be performed piecemeal. However, because liability is only joint, a debtor who fails does not make the others liable for his share as though solidarity existed.

The Civil Code adopts a practical approach: if one of the joint debtors fails to comply, the obligation is converted into one for damages, and those who were ready to comply are liable only for their proportional shares.

IX. Obligations with a Penal Clause

A penal clause is an accessory undertaking attached to an obligation to ensure performance by imposing a penalty in case of breach.

Example: “I will pay ₱100,000 on June 30; if I fail, I will pay an additional ₱20,000 as penalty.”

Nature and Purpose

The penalty serves to:

substitute for damages and interest in case of noncompliance, if there is no stipulation to the contrary;
compel performance;
liquidate damages in advance.

Rules

As a rule, the penalty substitutes for:

indemnity for damages, and
payment of interest

unless:

there is a contrary stipulation,
the debtor refuses to pay the penalty, or
the debtor is guilty of fraud.

Demandability of the Penalty

The penalty becomes demandable upon breach. However, courts may equitably reduce the penalty when:

the principal obligation has been partly or irregularly complied with, or
the penalty is iniquitous or unconscionable.

This power of reduction is very important in Philippine law, especially in loan, lease, and construction contracts.

X. Unilateral and Bilateral Obligations

Though not always listed as a formal Civil Code heading among the main classifications, this distinction is fundamental.

A. Unilateral Obligations

Only one party is bound.

Example: A simple loan after delivery, where the borrower alone is bound to repay.

B. Bilateral Obligations

Both parties are reciprocally bound.

Example: Sale: the seller must deliver, and the buyer must pay.

XI. Reciprocal Obligations

Reciprocal obligations are those arising from the same cause where each party is both debtor and creditor of the other.

Examples:

sale,
lease,
contract for a piece of work,
agency for compensation, in some respects.

Importance of Reciprocal Obligations

The rules on delay, rescission, and risk of loss are often different in reciprocal obligations.

Delay in reciprocal obligations

Neither party incurs delay if the other does not perform or is not ready to perform in a proper manner what is incumbent upon him. From the moment one party fulfills or is ready to fulfill, delay by the other begins.

Rescission

In reciprocal obligations, the injured party may generally choose between:

fulfillment, or
rescission,

in either case with damages.

This is the rescission under the Civil Code for reciprocal obligations, distinct from rescissible contracts under another part of the Code.

The power to rescind is implied in reciprocal obligations where one party fails to comply with what is incumbent upon him.

Courts generally decree rescission unless there is just cause authorizing a period.

XII. Real and Personal Obligations

This is another doctrinal way of classifying obligations.

A. Real Obligations

Those to give.

B. Personal Obligations

Those to do or not to do.

This distinction matters because the remedies differ:

specific delivery is central in real obligations;
substitute performance or undoing may govern personal obligations;
highly personal obligations often result in damages rather than compulsion.

XIII. Determinate and Generic Obligations

This is technically a sub-classification of obligations to give, but it deserves separate discussion because of its practical importance.

A. Determinate Obligations

The object is specifically designated.

Consequences:

debtor must preserve with proper diligence;
creditor may compel delivery of that exact thing;
loss through fortuitous event may extinguish the obligation, subject to exceptions.

B. Generic Obligations

The object is designated only by genus.

Consequences:

debtor may deliver any thing of the class of proper quality;
loss of any particular item does not extinguish the obligation;
creditor may have it performed at debtor’s cost.

Limited Generic Obligations

Sometimes the object is generic but limited to a certain class or stock.

Example: “One of my ten sacks of Dinorado rice.”

This may produce effects different from a purely unlimited genus, because the source is narrowed.

XIV. Legal, Conventional, and Penal Classifications by Source-Linked Structure

Although the “sources of obligations” are distinct from “classifications,” some related categories are often used in legal discussion.

A. Legal Obligations

Those arising from law.

Example: Tax obligations, support when provided by law, obligations imposed by statute.

B. Conventional Obligations

Those arising from contracts.

Example: Sale, lease, loan, agency.

C. Delictual or Quasi-delictual Obligations

Those arising from crimes or quasi-delicts.

They are still obligations under civil law because they may result in civil liability, restitution, reparation, indemnification, or damages.

This matters because not all obligations come only from contract.

XV. Principal and Accessory Obligations

A. Principal Obligations

Those that can stand independently.

Example: The obligation to pay the loan principal.

B. Accessory Obligations

Those attached to a principal obligation and dependent on it.

Examples:

mortgage,
pledge,
guaranty,
suretyship in relation to the principal debt,
penal clause,
interest stipulation.

If the principal obligation is void, accessory obligations usually fall with it, except in cases where the law treats the accessory undertaking independently under special rules.

XVI. Civil and Natural Obligations

This is a major Civil Code distinction.

A. Civil Obligations

Those that give a right of action to compel performance.

These are fully enforceable in court.

B. Natural Obligations

These are not based on positive law granting an action, but on equity and natural law. They do not grant a right of action to enforce performance, but once voluntarily performed, what has been delivered or rendered cannot generally be recovered.

Examples under the Civil Code include certain cases involving:

payment of a prescribed debt,
reimbursement by third persons after failed actions,
payment by minors in specific circumstances after annulment,
performance after civil obligation has become unenforceable.

Natural obligations are important because they occupy the middle ground between moral duty and legal compulsion. They are not judicially demandable, but the law gives effect to voluntary performance.

XVII. Moral Obligations Distinguished

A purely moral obligation is not the same as a natural obligation.

A moral obligation is based solely on conscience, with no legal effect.
A natural obligation is not judicially enforceable, but the law recognizes consequences when it is voluntarily fulfilled.

This distinction is significant in bar and classroom analysis.

XVIII. Positive and Negative Obligations

Another useful doctrinal classification:

A. Positive Obligations

Require the giving of a thing or performance of an act.

B. Negative Obligations

Require abstention or forbearance.

This matters in injunction cases and in determining whether an act done in violation may be undone.

XIX. Express and Implied Obligations

A. Express Obligations

Those clearly stated in law, contract, will, or judicial undertaking.

B. Implied Obligations

Those inferred from:

law,
equity,
usage,
the nature of the contract,
necessary consequences of stipulations.

Example: In sale, the seller’s obligation to preserve the item before delivery may arise even if not detailed in the contract, because the Civil Code supplies it.

XX. Immediate and Deferred Obligations

A. Immediate Obligations

Demandable at once.

B. Deferred Obligations

Demandability is postponed by a condition or period.

This is useful in distinguishing pure obligations from conditional and term obligations.

XXI. Possible and Impossible Obligations

A. Possible Obligations

Capable of performance legally and physically.

B. Impossible Obligations

Not capable of performance physically or legally.

Impossibility affects validity or extinguishment depending on whether it exists:

at the constitution of the obligation, or
after constitution without fault.

Initial impossibility may void the obligation. Supervening impossibility may extinguish it, especially in obligations to do, if performance becomes legally or physically impossible without debtor fault.

XXII. Classification According to Sanction or Enforceability

A. Enforceable Obligations

Those that can be compelled in court.

B. Unenforceable or Defective Obligations

Though more commonly studied under contracts, there are obligations that cannot be enforced because of:

lack of actionability,
prescription,
failure to comply with legal form in some contexts,
incapacity,
or operation of special rules.

Some of these may still produce effects if ratified or voluntarily performed.

XXIII. Monetary and Non-Monetary Obligations

A. Monetary Obligations

Obligations involving payment of money.

These are governed by important rules on:

legal tender,
inflation or deflation when extraordinary,
interest,
delay,
damages.

Simple loan or mutuum

Money borrowed becomes the property of the borrower, who must return an equivalent amount of the same kind and quality.

Interest

Interest is not due unless expressly stipulated in writing, except in cases of damages for delay or as allowed by law and jurisprudence.

B. Non-Monetary Obligations

These involve delivery of property or rendering/non-rendering of acts.

XXIV. Joint Indivisible, Solidary Divisible, and Other Combinations

A sophisticated understanding of obligations requires appreciating how classifications overlap.

A. Joint and Divisible

Each debtor owes only a proportionate share, and the prestation can be partially performed.

B. Joint and Indivisible

Each debtor is liable only for his part, but the prestation must be performed as a whole. Noncompliance tends to result in damages apportioned according to shares.

C. Solidary and Divisible

Though the prestation is divisible, each debtor may still be compelled to perform the whole because of solidarity.

D. Solidary and Indivisible

This gives the creditor maximum protection. Any debtor may be compelled to perform the whole indivisible prestation.

Example: A and B solidarily bind themselves to deliver a specific generator to X.

If performance becomes impossible through the fault of one solidary debtor, liability may extend to all as to the creditor, without prejudice to reimbursement among themselves.

XXV. Obligations Under Suspensive Condition Distinguished from Obligations with Suspensive Period

This distinction is often tested and frequently misunderstood.

Suspensive Condition

future and uncertain event
obligation becomes demandable only if event occurs

Example: “I will pay if the zoning permit is approved.”

Suspensive Period

future and certain event
obligation becomes demandable when the date arrives

Example: “I will pay on July 1.”

This difference affects:

whether rights already exist,
whether payment before event is recoverable,
risk allocation,
and the legal certainty of future demandability.

XXVI. Personal Rights and Real Rights in Obligations to Give

In an obligation to deliver, the creditor acquires a personal right against the debtor from the moment the obligation arises. But as a rule, he acquires a real right over the thing only upon delivery.

This distinction is central in Philippine civil law because a creditor under a contract of sale does not automatically become owner before tradition or delivery, unless special rules apply.

Thus, classification of obligations intersects with property law.

XXVII. Breach, Default, and Their Relation to Classification

The classification of an obligation matters because breach is not analyzed uniformly.

A. In obligations to give

The creditor may seek specific delivery or damages.

B. In obligations to do

The act may be done at debtor’s cost, or damages may be awarded.

C. In obligations not to do

The prohibited act may be undone if possible.

D. In reciprocal obligations

Delay generally begins only when one party performs or is ready to perform.

E. In solidary obligations

Any debtor may be sued for the whole.

F. In conditional obligations

Breach may not yet exist if the condition has not occurred.

G. In obligations with period

Demand before the arrival of term is premature unless the debtor has lost the benefit of the period.

XXVIII. Fortuitous Events and Classification of Obligations

Fortuitous event generally exempts the debtor when performance becomes impossible without fault. But the effect differs by classification.

In determinate obligations to give

Loss by fortuitous event may extinguish the obligation.

In generic obligations

It usually does not extinguish the obligation.

In obligations to do

Supervening impossibility without fault may extinguish the duty.

Exceptions

The debtor may still be liable even for fortuitous events:

when expressly stipulated,
when the law so provides,
when the nature of the obligation requires assumption of risk,
when the debtor is in delay,
when he promised to deliver the same determinate thing to two or more persons who do not have the same interest.

XXIX. Fraud, Negligence, Delay, and Contravention of Tenor

These are modes of breach applicable across classifications.

A. Fraud (Dolo)

Deliberate and intentional evasion of normal fulfillment.

Any waiver of future fraud is void. Liability for present or past fraud may be waived, subject to legal limitations.

B. Negligence (Culpa)

Failure to observe due care. The required diligence may be:

that stipulated,
that required by law,
or the diligence of a good father of a family if neither law nor stipulation fixes the standard.

C. Delay (Mora)

Delay is not mere lateness. It is legal delay after demand, unless demand is unnecessary under recognized exceptions.

Kinds:

mora solvendi: debtor’s delay
mora accipiendi: creditor’s delay
compensatio morae: delay of both parties in reciprocal obligations

D. Contravention of the Tenor

Violation of the terms of the obligation even if not amounting to fraud or negligence.

These forms of breach shape damages and remedies regardless of classification, but classification determines how they operate.

XXX. Damages and Remedies by Classification

A. Pure obligations

Immediate action for performance or damages.

B. Conditional obligations

Action depends on fulfillment or prevention of the condition.

C. Term obligations

Action accrues only upon maturity unless benefit of term is lost.

D. Alternative obligations

Need a valid choice and communication.

E. Facultative obligations

Only the principal prestation can be compelled before substitution.

F. Joint obligations

Recovery generally limited to proportionate shares.

G. Solidary obligations

Entire debt may be recovered from one debtor.

H. Divisible obligations

Partial performance may be relevant.

I. Indivisible obligations

Substantial noncompliance may justify damages or rescission.

J. Obligations with penal clause

Penalty may replace ordinary damages, subject to exceptions and equitable reduction.

XXXI. Common Bar and Classroom Distinctions

Several distinctions repeatedly arise in legal study:

1. Joint vs solidary

Joint liability is divided; solidary liability is entire.

2. Divisible vs indivisible

Divisibility concerns prestation; solidarity concerns parties.

3. Alternative vs facultative

Alternative: several prestations are due, one suffices. Facultative: only one prestation is due, substitute allowed.

4. Condition vs period

Condition is uncertain; period is certain.

5. Civil vs natural

Civil obligations are enforceable; natural obligations are not, but voluntary performance has legal effect.

6. Determinate vs generic

Specific thing vs class or genus; risk of loss differs sharply.

7. Reciprocal vs unilateral

Reciprocal obligations involve mutual prestations from the same cause.

XXXII. Philippine Practical Relevance

In Philippine legal practice, the classification of obligations matters in:

loan collection cases,
sale and delivery disputes,
construction and service contracts,
lease controversies,
family property settlements,
corporate undertakings,
surety and guaranty disputes,
real estate transactions,
damages actions,
rescission suits,
foreclosure-related obligations,
settlement agreements.

A lawyer, judge, or student who misclassifies the obligation may apply the wrong rule on demandability, delay, impossibility, damages, or parties’ liability.

XXXIII. Condensed Taxonomy of Classifications

For convenient review, obligations may be classified as follows:

According to prestation

to give
to do
not to do

According to perfection or demandability

pure
conditional
with a period

According to number of prestations

simple
alternative
facultative

According to number of parties and extent of liability

joint
solidary

According to susceptibility of partial performance

divisible
indivisible

According to sanction

with penal clause
without penal clause

According to relation of parties’ prestations

unilateral
bilateral
reciprocal

According to enforceability

civil
natural

According to object

determinate
generic

According to sign of conduct

positive
negative

According to dependency

principal
accessory

According to source-linked structure

legal
conventional
delictual/quasi-delictual

XXXIV. Final Synthesis

The classifications of obligations under Philippine civil law are not merely academic labels. They are working legal categories that determine when an obligation arises, when it can be enforced, how it may be performed, when it is extinguished, who may be sued, how much may be recovered, and what defenses may be raised.

A complete understanding requires seeing obligations not as isolated concepts but as interacting legal forms. A single obligation may simultaneously be:

reciprocal,
conditional,
solidary,
indivisible,
with a penal clause,
and to deliver a determinate thing.

Each classification contributes a rule. The legal task is to read them together.

In Philippine civil law, the architecture of obligations is built around a few central questions:

What exactly is due?
When is it due?
On what event does it depend?
Who may demand it?
Who must perform it?
Can it be partially performed?
What happens if it is breached, lost, delayed, or becomes impossible?

The classifications of obligations answer these questions. For that reason, they remain one of the most important and enduring parts of the Civil Code.