Can I Sue My Business Partner for Negligence?

Disputes between business partners often arise when one partner’s conduct causes financial loss to the company. 

While most partnership conflicts are addressed under contract law or fiduciary duties, negligence can also form the basis of a claim. 

Whether a negligence action is available depends on the nature of the conduct, the structure of the business relationship, and whether the partner owed a duty of care independent of contractual obligations.

Canadian courts have recognized that partners owe one another duties rooted in trust, confidence, and shared financial risk. When one partner’s careless actions cause harm to the business or to another partner personally, litigation may arise.

Negligence claims often appear in cases involving:

• Mismanagement of business finances
• Failure to maintain regulatory compliance
• Careless investment decisions
• Operational errors leading to litigation or penalties
• Failure to obtain necessary licenses or insurance

Negligence is a failure to take reasonable care, resulting in foreseeable harm to another person. It does not require intentional misconduct; instead, it focuses on whether the defendant acted below the standard expected in the circumstances.

To succeed in a negligence claim, a plaintiff must generally prove four elements:

1. Duty of Care – The defendant owed a legal duty to act with reasonable care.
2. Breach of Standard of Care – The defendant’s actions fell below what a reasonably prudent person would have done.
3. Causation – The breach caused the plaintiff’s loss.
4. Damages – The plaintiff suffered actual, compensable harm.

In a partnership, the duty of care is often clear: partners must act reasonably in managing the business.

It is important to distinguish negligence from intentional conduct.

Intentional wrongdoing involves:

• Deliberate actions
• Decisions made knowing they will cause harm
• Fraud, theft, misrepresentation, or intentional breaches of duty

Partnership disputes involving intentional misconduct are often addressed under:

• Breach of fiduciary duty
• Fraud or deceit
• Oppression in corporate contexts
• Civil conspiracy

A mistake is not automatically negligence.

A partner may make an error in judgment despite acting reasonably. Negligence requires a departure from the standard of care – not simply an imperfect outcome.

Examples:

Mistake:

• Making a decision that later turns out poorly despite due diligence.

Negligence:

• Making the same decision without reviewing available information or understanding the risks.

Courts assess whether the conduct was reasonable under the circumstances, not whether the business ultimately suffered a loss.

Yes: if the elements of negligence are met, and if the partner owed a legal duty of care independent of the partnership agreement.

Claims are most successful when:

• The negligent conduct clearly caused measurable financial harm
• The partner acted outside accepted business practices
• The conduct breached statutory obligations (e.g., safety, licensing, filing requirements)
• The amount of loss is significant
• The negligent conduct also breached fiduciary obligations

In many cases, negligence claims are brought alongside:

• Breach of contract
• Breach of fiduciary duty
• Oppression (in corporate structures)
• Accounting or equitable remedies

Before litigation, parties often evaluate:

• The terms of the partnership or shareholder agreement
• The scope of each partner’s responsibilities
• Whether the negligent conduct was a one-time error or ongoing mismanagement
• Availability of insurance (E&O or professional liability)
• Whether dissolution or winding up is preferable

In many cases, partnership disputes escalate quickly. Early legal advice is essential.

If your business partner’s negligence has caused financial loss, timely legal guidance is critical. Our commercial litigation lawyers assist clients in assessing negligence, breach of duty, and mismanagement claims between partners, shareholders, and co-owners. Contact us at 416.901.9984 or info@pintoshekib.ca.