1. The short, Philippine-law answer

A private company generally cannot impose a blanket prohibition on employees marrying co-workers if the consequence is dismissal or other severe penalty, because marriage is a constitutionally protected right and such policies usually fail the test of reasonableness and proportionality under labor law.

However, companies may regulate workplace relationships in narrow, job-related ways—especially where there are genuine conflicts of interest (e.g., supervisor–subordinate, auditors handling each other’s accounts, HR deciding each other’s cases), safety-critical roles, or integrity-sensitive positions. The legality depends on how the policy is written, what it aims to protect, and whether the restriction is the least intrusive way to do so.

2. Why this issue arises: “no-marriage,” “anti-fraternization,” and “conflict-of-interest” rules

Employers sometimes adopt policies that:

Ban marriage between co-workers outright (“no-marriage” rule).
Ban dating or romantic relationships at work (“anti-fraternization” rule).
Allow relationships/marriage but require disclosure or transfer if a conflict of interest exists (conflict-of-interest rule).

The legal treatment differs a lot between these categories. Philippine jurisprudence is most hostile to category 1 (blanket marriage bans), more skeptical but open to category 2, and most receptive to category 3 when tightly connected to legitimate business interests.

3. Constitutional and statutory backdrop

3.1 Constitutional protection of marriage and family

The Constitution treats marriage and family as social institutions deserving protection. This matters because workplace rules that effectively punish marriage are viewed as intruding into a fundamental liberty.

3.2 Labor Code and employer prerogative

Employers have management prerogative to set rules on hiring, discipline, and workplace conduct. But that prerogative is not absolute. It must yield to:

law and public policy,
good faith,
fairness and reasonableness, and
substantial relation to the job.

3.3 Equality and non-discrimination norms

While the Labor Code doesn’t have one catch-all anti-discrimination clause, Philippine law and jurisprudence strongly disfavor arbitrary classifications that penalize a protected personal status (like marriage) unless business necessity is clear and the rule is narrowly tailored.

4. The leading Supreme Court approach

Philippine Supreme Court decisions addressing marriage-related workplace rules share a core theme:

A rule that penalizes employees for marrying a co-worker is invalid unless the employer proves a legitimate, job-related purpose and uses the least restrictive means.

4.1 What the Court typically rejects

The Court has repeatedly frowned on policies that:

forbid marriage per se,
force resignation upon marriage, or
treat marriage as misconduct.

Why?

Marriage is a fundamental right.
A blanket ban is often overbroad.
The employer usually has less restrictive options to address its concerns (e.g., transfer, re-assignment, disclosure).

4.2 What the Court may accept

The Court is more sympathetic to policies that:

target specific roles where a relationship creates demonstrable risk (conflict of interest, security, safety, or integrity),
do not automatically terminate employees for marrying, and
offer reasonable accommodations such as transfer, change of reporting lines, or role recusal.

5. Legal tests that matter in practice

When deciding legality, tribunals commonly look at these:

5.1 Legitimate business interest

The employer must show a real interest—examples:

prevention of conflict of interest (e.g., spouse evaluating spouse),
protection of confidentiality or integrity (finance, audit, sensitive investigations),
avoidance of favoritism or coercion,
ensuring workplace safety in high-risk environments,
compliance with industry regulation (e.g., banking fit-and-proper or segregation-of-duties norms).

A vague claim like “we don’t want drama” or “it’s bad for morale” is usually insufficient on its own.

5.2 Reasonableness and proportionality

Even with a valid aim, the rule must be:

reasonable,
not oppressive, and
proportional to the risk.

A total ban is almost always seen as disproportionate.

5.3 Least restrictive means

If the goal can be achieved by:

disclosure,
transfer,
altering supervisory lines,
conflict-recusal procedures, or
targeted restrictions,

then a full “no-marriage” rule is too extreme.

5.4 Due process in termination

Even if a policy is valid, dismissal must still satisfy:

substantive due process (just/authorized cause), and
procedural due process (notice and hearing).

Marriage itself is not a just cause under Article 297 (formerly 282). So termination based purely on marrying a co-worker is legally fragile.

6. Distinguishing marriage bans from conflict-of-interest rules

6.1 Blanket marriage bans

High legal risk. Almost always struck down if the penalty is dismissal.

Problem: They regulate status, not work-related risk.

6.2 Marriage allowed but with safeguards

Much more defensible if tailored:

“Employees may marry co-workers, but spouses cannot be in a direct reporting relationship; one will be transferred to an equivalent role.”

This targets the risk rather than the relationship itself.

6.3 Dating/romance bans

Mixed legality. A flat ban on all romantic relationships may still be overbroad, but narrower “anti-fraternization” policies can stand if:

they apply only to high-risk pairings (e.g., manager–subordinate), or
they focus on conduct affecting work (harassment, retaliation, favoritism), not private life.

7. Industry examples: when restrictions are more likely valid

Banking/finance/audit
- “Spouses cannot handle each other’s accounts or reviews; segregation of duties is required.”
Human resources / disciplinary roles
- “Spouses cannot sit in decisions involving each other; recusal required.”
Safety-critical operations
- “Two spouses cannot be assigned simultaneously to the same live-safety post where collusion or distraction creates measurable danger.”
Security and law-enforcement-type private roles
- “Relationships must be disclosed if they compromise investigations.”

In these, the conflict is job-linked and evidence-based, not moral or social.

8. What employers can do legally (best-practice design)

A policy is more likely to survive challenge if it:

Affirms the right to marry.
Requires conflict disclosure.
Defines conflict-of-interest situations clearly (direct reporting, audit oversight, custody of funds, etc.).
Offers neutral remedies:
- transfer to equivalent post,
- change of supervisor,
- re-allocation of sensitive tasks.
Uses objective standards, not discretionary moral judgment.
Protects against retaliation and ensures confidentiality.

9. What employees can do if disciplined for marrying a co-worker

If a company imposes discipline or dismissal because of marriage, an employee may:

File an illegal dismissal case with the NLRC.
Seek reinstatement and backwages if termination is found illegal.
Argue that the policy is:
- unconstitutional in effect,
- against public policy favoring marriage,
- unreasonable / overbroad, and
- not a just cause for termination.

Remedies depend on proof and circumstances, but jurisprudence trends favor employees in blanket-ban scenarios.

10. Practical risk map

“You may not marry anyone in the company; if you do, you’re fired.” → Very likely invalid.
“You may marry, but spouses can’t be in a supervisor-subordinate chain; we will transfer one to a comparable role.” → Often valid, if applied fairly.
“If you marry a co-worker, one must resign.” → Usually invalid (coercive and overbroad).
“Romantic relationships must be disclosed if they create conflicts; favoritism/harassment is prohibited.” → Generally valid.

11. Key takeaways

Marriage is a protected right, and labor law disfavors employer rules that punish it.
Blanket “no-marriage” policies are almost always unlawful if they lead to termination or forced resignation.
Employers can regulate conflicts of interest, not marriage itself.
The winning formula for legality is legitimate aim + narrow scope + least restrictive remedy + due process.
Employees disciplined solely for marrying a co-worker have strong grounds for illegal dismissal or unfair labor practice claims, depending on facts.

12. Sample policy language (for illustration)

“The Company respects employees’ right to marry. However, to prevent conflicts of interest, spouses or partners shall not be placed in direct reporting relationships nor assigned to roles where one audits, supervises, or decides on matters affecting the other. Employees are required to disclose such relationships to HR for appropriate, non-punitive re-assignment or restructuring. No employee shall be dismissed solely by reason of marriage.”

This kind of framing aligns with constitutional values and labor-law reasonableness.

If you want, I can also draft two versions of a compliant PH-context policy (strict vs. light-touch), or outline arguments for either side in an NLRC case.