Atty. Rainier Mamangun cover photo

Atty. Rainier Mamangun's Law Office is a full-service firm that provides a full range of legal services for any activity or venture, or any area of interest or concern in the Philippines. Guided by traditional values, but oriented towards present-day solutions, his law firm is composed of lawyers and advocates with diverse and extensive experience in all areas of Philippine law.

We provide a full range of legal services for any case, concern, or interest that you may have.  Our Law Firm has been in existence for over 18 years having been established in 2004.  We have handled thousands of cases in various areas of the law which means we would not be "learning as we go" when we attend to your case.

Our Team of lawyers, paralegals, interns, and support staff are properly trained, skilled in their line of work, and are dedicated to their craft. Coming from various fields of expertise, we harness our people's  individual strengths and utilize them to the fullest in the pursuit of the client's cause.   

You are not just "another" client of the Firm.  Embedded in our culture is the genuine concern for the client's situation. Thus, we tailor fit our actions to respond to your specific needs. Given the pandemic and its impact on people's finances, we also understand the need for  reasonable and flexible rates while maintaining the quality of service that we provide.   

Atty. Rainier Mamangun's expertise in family law and domestic relations covers representation and advisory services in annulment, declaration of nullity of marriage, recognition of foreign divorce, child custody, spousal and child support, adoption, and domestic abuse cases, among others. For almost two decades, he has worked on over 200 family law-related cases. He also handles real property and business law cases.

Atty. Rainier Mamangun is adept at handling cases in and out of court. His training with the Philippine Department of Foreign Affairs enabled him to hone his diplomatic skills which now prove crucial in his dealings and negotiations with the court and the opposition. His skills at legal drafting and the defense of existing legislation were developed through years of service at the Office for Migrant Workers Affairs and in appearances at Congressional hearings and various inter-agency meetings that dealt with law and policy formulation relating to the welfare of Filipinos overseas. 


About Atty. Rainier Mamangun

Founded in 2004

6 Offices

25 people in their team

Reveal phone Website
Practice areas
Employment & Labor
Lawsuits & Disputes
Real Estate
Intellectual Property

Languages spoken

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Practice areas


With over three hundred family-related cases, including nullity of marriage, annulment, adoption, custody, and support, we have a deep understanding of both the law and the needs of the client.  Our attorneys work to guide our clients through times of crisis, and we find creative solutions that allow them to move forward in their lives. We understand that these cases are more than legal issues, and we recognize that we are dealing with our clients’ emotional well-being as well.

Divorce & Separation


We provide general corporate and retainer services to domestic and foreign enterprises, where we bridge the gap between the letter of the law and the demands of doing business in the Philippines. Our diversified and customizable corporate services ensure that our clients’ concerns are addressed efficiently by a team dedicated to a specific specialist practice area.

Our corporate services include contract and policy review, corporate secretarial and corporate housekeeping services, director services, corporate governance advisory and compliance, regulatory compliance, and industry-specific counseling. In all of these services, we provide legal insight with business instinct.  We help position our clients’ businesses to succeed, and aim to protect and prepare them for future circumstances.

Guided by years of experience and involvement in diverse foreign and domestic investments and businesses, we provide legal and tax advice relating to the corporate structure best suited to your needs. Our incorporation and post-incorporation services are customizable to achieve cost-effective results.

Apart from procuring permits and licenses from local government units and the Bureau of Internal Revenue, we help clients secure fiscal and non-fiscal incentives from the Bureau of Investments, the Philippine Economic Zone Authority, the Cagayan Economic Zone Authority and other regulatory agencies.

Business Registration

Employment & Labor

Our services span across several facets of labor law. We represent clients in both employee claims and employer defense.

Our primary objective is to avoid expensive and protracted litigation if possible. To this end, we provide advisory services to employers relative to labor standards, employee termination, contractual and other types of employment, and other concerns affecting the workplace. Our advisory services include the preparation of law-mandated policies and manuals, and employment contracts suited to the needs of the employer’s business.

Our expertise has been shaped by years of experience in labor dispute resolution and labor litigation. Through the Single Entry Approach of the Department of Labor and Employment, we aim for a fair and equitable settlement. Where a peaceful resolution is not possible, we provide representation before the National Labor Relations Commission, the Court of Appeals and the Supreme Court on a wide spectrum of issues, including illegal dismissal, constructive dismissal, unfair labor practices, non-payment of wages, and other cases involving a violation of labor standards.

Labor Law

Lawsuits & Disputes

Our litigation services cover a broad range of cases. We represent individuals as well as companies in civil, criminal and commercial disputes before regular courts, special courts and alternative dispute resolution centers in the Philippines.

With strong and steady leadership from our Senior Partners, we offer litigation services relating to family law, criminal cases and investigations, torts and damages, commercial disputes, money claims, medical malpractice, and alternative dispute resolution. We also offer services relevant to wealth perpetuation and settlement of large estates.

Our litigators are not only your lawyers. Our corporate clients appreciate our understanding of the technical and commercial aspects of every dispute we undertake; while our individual clients value the time that we devote and the cost-effective solutions we promote to resolve their concerns.


Real Estate

We provide advisory, due diligence and litigation services for real estate transactions and special land issues. Our services cover the preparation and review of contracts, agreements and instruments relating to the purchase and acquisition of real properties, including purchases by foreign nationals of condominium units in the Philippines, and the transfer and registration of certificates of title.

Our lawyers have also assisted several real estate developers in the formation of legal policies and strategies and the preparation of registration documents pertaining to various condominium projects and developments in the country. 

Our years of experience in the area of real estate permit us to address our clients’ concerns and facilitate a cost-efficient and expeditious resolution of disputes and achievement of their objectives.

Housing, Construction & Development


Navigating immigration and visa requirements can be daunting. Seasoned by experience, our immigration team will help steer you through the extensive paperwork and deliver results at a reasonable cost.

We provide legal services and visa processing assistance to foreign nationals, employees, executives and businesses. After years of working with the Bureau of Immigration, the Department of Labor and Employment and the Philippine Retirement Authority, our immigration team has developed the skill set and practical knowledge that delivers efficient end-to-end services.


Retirement Visa

Intellectual Property

We provide assistance in the registration of intellectual property, and in the enforcement of copyright and intellectual property laws in the Philippines. We also offer a broad range of information technology and e-commerce services, which include advisory and contract negotiation  services pertaining to licensing agreements, technology investing and joint ventures.  


Our Partners and Associates

Atty. Rainier Mamangun

Senior Partner